Add stub specs for some generic nodes

* Still more nodes to add, but I wanted to take a break but didn't
  want to wait to add these.
Add coveralls to mutant
Add magic encoding header to all ruby files

* rubocop still warns about this on ruby 1.9.3, so it was fixed so
  it produces less output on travis.
Fix rubocop warnings in gemspec

* Add bundler as a development dependency
Upgrade unparser gem dependency

* Fix failing "canary" specs
* Not all mutations can be performed yet for rescue, but this is an
  improvement since it does not raise an exception.
Update code to be simpler
Upgrade unparser gem dependency

* Fix now (partly) passing specs
Replace global variable with string literal
Update IRC channel
Update travis IRC notifications
Upgrade unparser gem dependency
Fix failing spec caused by bug fix in unparser
Update travis config to track coverage properly in jruby

* Update latest bundler to install and exclude unnecessary gems
  from the gemfile
Add jruby-head to list of rubies to allow failures
Update reason that ruby-head allows failures
Update unit test time threshold to 5 seconds

* No test should take this long, but I am seeing weird failures on
  travis with 1.9.3, so I want to find a threshold that works 100%
  of the time.
Add encoding to ruby files
Update path name to report the filename better on failure
Fix whitespace
Add rspec profiling and turn on warnings in specs