remove ordereddict dependency, issue #55

[yosukesan]

Locally tested on my env. All unit test passed.

Test result

$ uname -a && grep VERSION /etc/os-release  && pytest-3 
Linux localhost 5.10.0-20-amd64 #1 SMP Debian 5.10.158-2 (2022-12-13) x86_64 GNU/Linux
VERSION_ID="11"
VERSION="11 (bullseye)"
VERSION_CODENAME=bullseye
============================= test session starts ==============================
platform linux -- Python 3.9.2, pytest-6.0.2, py-1.10.0, pluggy-0.13.0
rootdir: /home/yosuke/Data/github/python-xbrl
collected 15 items                                                             

tests/test_parse.py ...............                                      [100%]

============================= 15 passed in 11.67s ==============================

requirements.txt

$ for pkg in $(cut -f 1 -d '=' requirements.txt | cut -f 1 -d '>'); do python3 -m pip list | grep  $pkg ; done
pytest                   6.0.2
marshmallow              3.10.0
beautifulsoup4           4.9.3
lxml                     4.6.3
six                      1.16.0