Remove Deprecated ExtractGraph app

[greebie]

GitHub issue(s):

#291

What does this Pull Request do?

Removes ExtractGraph which was previously deprecated. ExtractGraphX is the current replacement.

How should this be tested?

Travis / codecov should suffice.

Interested parties

@ianmilligan1 @ruebot

Thanks in advance for your help with the Archives Unleashed Toolkit!

[codecov-io]

Codecov Report

Merging #293 into master will increase coverage by 2.36%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #293      +/-   ##
==========================================
+ Coverage   73.39%   75.76%   +2.36%     
==========================================
  Files          42       41       -1     
  Lines        1184     1147      -37     
  Branches      210      202       -8     
==========================================
  Hits          869      869              
+ Misses        244      209      -35     
+ Partials       71       69       -2

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[ianmilligan1]

Builds nicely locally too.

I don't think we've had any real use of the ExtractGraph functionality, and there's the newer ExtractGraphX. Given all this, I think this is a good removal for 0.18.

[ianmilligan1]

And just to link this to the PR where the deprecated notice was included, so this shouldn't be a surprise to anybody: https://github.com/archivesunleashed/aut/pull/245/files