remove internal use of rvm in rvm
make sure to unload broken rvm before doing any cli action
fixed aliases handling
move the environment fix up earlier in the rvm cli
allow nesting of rvm when in __rvm_load_project_config
read ruby from GEM_HOME when no rvm_ruby_string when using @gemset
allow to ignore rubygems installation, fix #2504
Merge pull request #2501 from wayneeseguin/features/do_not_use_rvm_in_rvm_gh_issue_2501

RVM removes what it shouldn't remove
improved cleaning list of gems to remove from installation
fix filtering gems to install from global/default gems lists, for you @joshk
do not parse ruby name when it is already installed, fix #2503