Allow for comparisons of the module's versions in the expression of dependencies. For example one can now say "itop-config-mgmt/>=2.0.2" for a dependency.

git-svn-id: http://svn.code.sf.net/p/itop/code/branches/2.0.1@2854 a333f486-631f-4898-b8df-5754b55c2be0