PROV-1092 Starting point for intermediate export download configuration screen

Renaming the download already works for batch exports (i.e. via sets)
and single-item exports. Next up: Running exports based on search
results through the same controller. No need to keep that code in two
different places.
Merge branch 'develop' into dev/exportUIRework

* develop:
  PROV-1093 Fix set display in history menu
PROV-1092 Move batch export from search result to central batch export controller

This should help streamline the export code in preparation for
alternative export targets.

Still have to figure out how to pass result order/sorts to batch
exporter. The order seems to be all over the place right now if we just
pull the list from ResultContext.
Merge branch 'develop' into dev/exportUIRework

* develop:
  PROV-1095 Now update ResultContext properly if result order has changed
PROV-1092 Work on inspector
PROV-1092 Add GitHub PHP API
PROV-1092 Remove GitHub PHP API

This one doesn't quite follow the GitHub API v3 and documentation is
sparse.
PROV-1092 Install GitHub PHP API via composer
PROV-1092 First version of GitHub export upload. Very sketchy and barfs on first sight of an error, but it works.
NOJIRA Add guzzle
PROV-1092 Code refactoring and exception handling
PROV-1092 Handle overwriting existing files in GitHub
PROV-1092 Config defaults
PROV-1092 Proper error and filename handling
PROV-1092 Update default config
PROV-1092 Very rough first version of ajax based export destination screen

It uploads to GitHub okay for single item exports. Download is still
broken and batch exports are probably totally broken too right now.
NOJIRA Added some ActionController phpdoc so IDEs can do their thing
NOJIRA No more magic method calls in this controller
PROV-1092 First cut at file download
PROV-1092 Clean up tmp dir once in a while