Various issues with running the RGL test suite

[Kaljurand]

RGL-related tests seem to be located in at least 3 different places (which is confusing):

• lib/tests
• lib/treebanks
• testsuite/libraries

The gold-standard testsuite/libraries/exx-resource.gfs.gold covers just 3 languages.

Running cabal test fails (at least under my setup) with:

cabal: You need to re-run the 'configure' command.
The version of Cabal being used has changed (was Cabal-1.22.5.0, now Cabal-1.22.2.0).
Additionally the compiler is different (was ghc-7.10, now ghc-7.6)
which is probably the cause of the problem.