Dockerize and enable excalibur to run as a hosted service

[aakashlpin]

• Fixes opencv dependency issue
• Add a Dockerfile that can build from latest master
• Added a sample Github action to demo how to deploy it to DigitalOcean

[answerquest]

@aakashlpin I ran your repo/Docker file:

docker build -t excalibur1 .

And its erroring out that the pip3 install stage:

Processing /home/root/excalibur
Collecting Click>=7.0 (from excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/48/58/c8aa6a8e62cc75f39fee1092c45d6b6ba684122697d7ce7d53f64f98a129/click-8.0.3-py3-none-any.whl (97kB)
Collecting Flask>=1.0.2 (from excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/8f/b6/b4fdcb6d01ee20f9cfe81dcf9d3cd6c2f874b996f186f1c0b898c4a59c04/Flask-2.0.2-py3-none-any.whl (95kB)
Collecting SQLAlchemy>=1.2.12 (from excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/bf/a7/d7c0f4d372bc73520f40453eb6e18bd712aac24a4fa78ca0d321b231acb8/SQLAlchemy-1.4.27-cp36-cp36m-manylinux_2_5_x86_64.manylinux1_x86_64.manylinux_2_12_x86_64.manylinux2010_x86_64.whl (1.6MB)
Collecting Werkzeug<1.0.0 (from excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/c2/e4/a859d2fe516f466642fa5c6054fd9646271f9da26b0cac0d2f37fc858c8f/Werkzeug-0.16.1-py2.py3-none-any.whl (327kB)
Collecting camelot-py[cv]>=0.7.1 (from excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/3a/d3/08ae34725925bdaf85be36be7a230ba3ed7d6ae8e49a2276f1753620f347/camelot_py-0.10.1-py3-none-any.whl (40kB)
Collecting celery>=4.1.1 (from excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/06/9d/61976ecc8caf0a03357bd174fa23c43b9dcd85f4c9667aa692de361cae84/celery-5.1.2-py3-none-any.whl (401kB)
Collecting configparser<3.6.0,>=3.5.0 (from excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/55/c0/e0206081eaad646c6f5e2dc266edf457110d9031b363518d3264880e675d/configparser-3.5.3-py3-none-any.whl
Collecting opencv-python==4.2.0.34 (from excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/72/c2/e9cf54ae5b1102020ef895866a67cb2e1aef72f16dd1fde5b5fb1495ad9c/opencv_python-4.2.0.34-cp36-cp36m-manylinux1_x86_64.whl (28.2MB)
Collecting importlib-metadata; python_version < "3.8" (from Click>=7.0->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/c4/1f/e2238896149df09953efcc53bdcc7d23597d6c53e428c30e572eda5ec6eb/importlib_metadata-4.8.2-py3-none-any.whl
Collecting Jinja2>=3.0 (from Flask>=1.0.2->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/20/9a/e5d9ec41927401e41aea8af6d16e78b5e612bca4699d417f646a9610a076/Jinja2-3.0.3-py3-none-any.whl (133kB)
Collecting itsdangerous>=2.0 (from Flask>=1.0.2->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/9c/96/26f935afba9cd6140216da5add223a0c465b99d0f112b68a4ca426441019/itsdangerous-2.0.1-py3-none-any.whl
Collecting greenlet!=0.4.17; python_version >= "3" and (platform_machine == "aarch64" or (platform_machine == "ppc64le" or (platform_machine == "x86_64" or (platform_machine == "amd64" or (platform_machine == "AMD64" or (platform_machine == "win32" or platform_machine == "WIN32")))))) (from SQLAlchemy>=1.2.12->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/76/5a/a6a693096353c1c17932b21ae864a0280e420fadd2f14399a00b085d3d1b/greenlet-1.1.2-cp36-cp36m-manylinux1_x86_64.whl (162kB)
Collecting numpy>=1.13.3 (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/45/b2/6c7545bb7a38754d63048c7696804a0d947328125d81bf12beaa692c3ae3/numpy-1.19.5-cp36-cp36m-manylinux1_x86_64.whl (13.4MB)
Collecting PyPDF2>=1.26.0 (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/b4/01/68fcc0d43daf4c6bdbc6b33cc3f77bda531c86b174cac56ef0ffdb96faab/PyPDF2-1.26.0.tar.gz (77kB)
Collecting tabulate>=0.8.9 (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/ca/80/7c0cad11bd99985cfe7c09427ee0b4f9bd6b048bd13d4ffb32c6db237dfb/tabulate-0.8.9-py3-none-any.whl
Collecting pandas>=0.23.4 (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/c3/e2/00cacecafbab071c787019f00ad84ca3185952f6bb9bca9550ed83870d4d/pandas-1.1.5-cp36-cp36m-manylinux1_x86_64.whl (9.5MB)
Collecting chardet>=3.0.4 (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/19/c7/fa589626997dd07bd87d9269342ccb74b1720384a4d739a1872bd84fbe68/chardet-4.0.0-py2.py3-none-any.whl (178kB)
Collecting openpyxl>=2.5.8 (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/1c/a6/8ce4d2ef2c29be3235c08bb00e0b81e29d38ebc47d82b17af681bf662b74/openpyxl-3.0.9-py2.py3-none-any.whl (242kB)
Collecting pdfminer.six>=20200726 (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/51/2b/0a3329605203de8df990ff5427a145dc81ea3e0eff0046424d1d306d1b29/pdfminer.six-20211012-py3-none-any.whl (5.6MB)
Collecting ghostscript>=0.7; extra == "cv" (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3)
  Downloading https://files.pythonhosted.org/packages/89/5b/fa8ac3997ae33d631179ea2e972a5db358d5418b8cccbecfa4dc4c1f3b77/ghostscript-0.7-py2.py3-none-any.whl
Collecting pdftopng>=0.2.3; extra == "cv" (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3)
  Could not find a version that satisfies the requirement pdftopng>=0.2.3; extra == "cv" (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3) (from versions: 0.1.0)
No matching distribution found for pdftopng>=0.2.3; extra == "cv" (from camelot-py[cv]>=0.7.1->excalibur-py==0.4.3)
The command '/bin/sh -c cd excalibur   && ls -lah   && pip3 install .   && cd ../' returned a non-zero code: 1