build a debug version of cvmfs_unittests
add relaxed matching to pathspec
TEST: unit test relaxed matching
relaxed matching for negative dirtab rules
TEST: T_Dirtab.MultiDirectoryWildcardsInNegativeRules
Refactor: remove code duplication
remove dead code
TEST: integration test for wildcard negations
Merge pull request #518 from reneme/fix-relative_negative

Fix: Negative Dirtab Entries With Wildcards

(bypassing Jakob to have a Cloud Test result of that by tomorrow)

This adds the possibility to have negative .cvmfsdirtab entries that are non-absolute paths with wildcards. Something like:

! *.svn
This will prevent CernVM-FS to create any nested catalogs inside a .svn directory.
See Jira ticket CVM-639.

Note: This Pull Request contains Pull Request #517.