Feature/add review pr option

[nudded]

use ./eb --review-pr 1017 -D | less -R to try this out.
TODO:

• Compare with other files found in the same PR
• add legend on top
• add documentation / docstrings
• figure out how to display added/removed spaces

[hpcugentbot]

Automatic reply from Jenkins: Can I test this?

[boegel]

Jenkins: ok to test

[boegel]

briefly explain the heuristic used, rename function to find_relatd_easyconfigs

[fgeorgatos]

Please expand the above; I was compelled to ask Ken on what is this about, so, here are some ideas:

[10:39:11] <boegel> fotis2: --review-pr 123 # will compare all easyconfigs touched in PR #123 with current develop, and give an enhanced diff report
[10:39:59] <boegel> fotis2: for each easyconfigs, it will try and find a set of closely related easyconfigs (some software + e.g. same version + toolchain name), and show the differences in a summary view

[boegel]

Current version can't handle easyconfigs that were deleted (which shouldn't occur, but fine):

ERROR: EasyBuild crashed with an error (at easybuild/tools/github.py:334 in
fetch_easyconfigs_from_pr): Not all patched files were downloaded to
/tmp/easybuild-FnFCKn/tmpH83hi7: ['Cube-4.2.3-goolf-1.5.14.eb', 'OPARI2-1.1.2-goolf-1.5.14.eb',
 'OTF2-1.2.1-goolf-1.5.14.eb', 'PAPI-5.2.0-goolf-1.5.14.eb', 'PDT-3.20-goolf-1.5.14.eb',
'Qt-4.8.4-goolf-1.5.14.eb', 'Score-P-1.2.3-goolf-1.5.14.eb', 'binutils-2.22-goolf-1.5.14.eb',
'null'] vs
['binutils-2.22-goolf-1.5.14.eb', 'Cube-4.2.3-goolf-1.5.14.eb', 'null', 'null',
'OPARI2-1.1.2-goolf-1.5.14.eb', 'OTF2-1.2.1-goolf-1.5.14.eb', 'PAPI-5.2.0-goolf-1.5.14.eb',
'PDT-3.20-goolf-1.5.14.eb', 'Qt-4.8.4-goolf-1.5.14.eb', 'Score-P-1.2.3-goolf-1.5.14.eb']

I'm also not sure what the nulls are about?

[fgeorgatos]

I haven't looked at the rest of the code, so maybe this is redundant:
wouldn't not ==1 do the job better, to catch the empty case?

[fgeorgatos]

overall good, thanks for the PR!