Fix macro indentation rule specifiers
Add built in support for C++ and Java
Add macro for user to add additional language support

`smart-tabs-add-language-support` allows a user to add a new
language to `smart-tabs-insinuate-alist` easily. Has the same
signature as `smart-tabs-create-language-advice` and uses that
macro internally.
Modified documentation to reflect changes
Merge Matt Renaud’s add-language-support feature

Closes #23.
Credit Matt Renaud and bump version
Correct my rôle in this project
Rearrange documentation a bit