switch railsexpress to urls
make gemset_use a separate action
control display Using with rvm_use_flag
Merge pull request #1705 from wayneeseguin/bugfix/display_using_ruby_for_new_project_files

bring back the "Using ruby-1.9.3-p392 with gemset gem" line when switching directories
Merge pull request #1818 from wayneeseguin/features/remote_railsexpress

switch railsexpress to urls
Support more Gentoo package managers

* Portage
* Paludis
* PkgCore
Merge pull request #1801 from cheba/gentoo-pakcage-managers

Support more Gentoo package managers
remove git requirement from default libs set for ruby on gentoo, update #1801