Revert "remove rvm_silence_path_mismatch_check_flag from rvmrc on travis for rvm-test-rvm1/path_mismatch_comment_test.sh"

This reverts commit bc3f2ca7c843624cf43aad861ec624eb7b27acd3.
cleaning __rvm_ruby_string
cleaning tools_strings
speed up and clean selector
speed up and clean selector