added single/global replacement and case insensitivity
add a test class for MeantToSay
add third string for older tests in meant_to_say
fix reference error with flags, defaulting to 0
use py2.6 compatible substitution

By compiling with re.I and then doing the substitution from that
object. If the `i` flag is not found, fallsback to normal `compile`
Merge pull request #97 from alfredodeza/master

Tests and fixes for issue #94