Removing appraisal gemfile locks

There is no reason to keep them. Just as we don't keep Gemfile.lock for a gem,
there is no point in enforcing particular version of gems when testing
different versions of rails with appraisal.

Author: jtmalinowski

.gitignore

@@ -2,3 +2,5 @@
 Gemfile.lock
 *.log
 test/dummy/tmp
+
+gemfiles/*.gemfile.lock