update .travis.yml to exclude 'master'.
Update .travis.yml, backport spec fix for 2.0+
Remove Guard
Fix singleton class test for 2.1.0
Backport rbx fixes from master
Defer Readline load as long as possible (fix #1081, #1095)

Also fixes rweng/pry-rails#50 and rails/spring#244.
Merge pull request #1103 from pry/0-9-12-defer-readline

Defer Readline load as long as possible (fix #1081, #1095)
Bump to v0.9.12.5

This version includes a compatibility fix for Spring when Ruby is
compiled with libedit instead of readline.
If bond gem is not installed even in readline environment, use InputCompleter as a pry completer

Closes #1106
Merge pull request #1108 from yasuoza/fix/1106

If bond gem is not installed even in readline environment, use InputCompleter as a pry completer
version bump to 0.9.12.6