specidentify notebook

[HeloiseS]

• [x] Make it explicit that the example data in the notebook should be exer211.tar.Z. They just need to download it to the directory where the notebook is and extract it there.
• [x] Tell the reader of the notebook to check that the files in the exercises/spec/ folder have a .fits extention, and if they don't they need to rename the files. In bash they can use for file in *fsp*; do mv "$file" "$file.fits"; done in the directory.
• [x] Actually it seems the fps00* (present in exer211.tar.Z) and sp00* files (refered to in the notebook), might not even be the same thing.
• [ ] Add dependencies somewhere: PyQT4 (pyqt=4), scipy, matplotlib, astropy, ccdproc, numpy
• [x] complete comment:

# setup the data and correct for the orientation of the data
# so that it is [aligned with the x axis]

• [ ] The save button in the GUI does not seem to do anything. It would be nice to know what it does. Also if it could save a readable output into a database folder (for example), that could be nice.

• [ ] When trying to undelete a point in the GUI with "u", it does not necessarily undelete the right point if there are two points very close together horizontally (even if very well spaced vertically).

• [ ] The question mark help button "?" does not work on the Image tab, but works on the Arc and the Residual tab. I narrowed it down to line 863+ in https://github.com/crawfordsm/specidentify/blob/7c148b9b8c4770b77bdeba3b1d67ffecb5607b0d/specreduce/interidentify.py#L863

=> It seems like only the arcfigure and errfigure call onKeyPress.