adding Gems ignores

Ruby.gitignore

@@ -0,0 +1,22 @@
+.DS_Store
+*.tmproj
+tmtags
+*~
+\#*
+.\#*
+*.swp
+.*.swp
+coverage
+rdoc
+pkg
+test/tmp
+test/version_tmp
+tmp
+pkg
+*.gem
+*.rbc
+lib/bundler/man
+spec/reports
+.config
+InstalledFiles
+.bundle