Travis test 1.9.2 and 2.0.0 also

Signed-off-by: Michael Barton <mail@michaelbarton.me.uk>
Update to latest versions of gems

Signed-off-by: Michael Barton <mail@michaelbarton.me.uk>
Explicitly require yaml

Signed-off-by: Michael Barton <mail@michaelbarton.me.uk>
Slim down Rakefile contents

Signed-off-by: Michael Barton <mail@michaelbarton.me.uk>
Fix race condition by disabling garbage collection

Signed-off-by: Michael Barton <mail@michaelbarton.me.uk>
Merge branch 'feature/ruby-2.0.0' into release/0.2.0
Bump minor version

Signed-off-by: Michael Barton <mail@michaelbarton.me.uk>
Merge branch 'release/0.2.0'

  * Make sure compatible with ruby 2.0.0
  * Update all gems
  * Fix race condition when using temporary files in specs

Signed-off-by: Michael Barton <mail@michaelbarton.me.uk>