Remote backports dependency

Since the syntax depends on 1.9 mode, we can remove this dependency.
This saves us another 10 bytes from the source which is over 1% of the
entire almost Sinatra codebase.

I of course haven't tested this change, for that we have users to
verify that it works.
Make Travis happy.

I don't like it when Travis is sad. :'(
String interpolation is even shorter
Merge pull request #13 from grddev/master

Save a space by using string interpolation
Merge pull request #10 from dbussink/master

Remove another 1% of the code
Merge pull request #12 from steveklabnik/master

Save TravisBot
Update README.md
seven lines
six lines
fix things
add LICENSE
Improve clarity