Properly parse provides for gems in /usr/lib (CNY-3869)

Strip provision of "/gems/" and earlier before stripping "/lib/" and
earlier.
Adjust the RubyDependency depFormat (CNY-3869)

Ruby deps use /-characters as a separator, so the default depFormat is
incorrect.
Merge branch 'stable' into feldspar
Revert "Merge branch 'stable' into feldspar"

This reverts commit 8ee18d07934b25b81510dca27e98eb686f6a775c, reversing
changes made to 8fb0f2a0775f9acd87a5ab581d3db4552a7fb254.