Bug 843592 - Add Lohit fonts for Indic script support in B2G

This adds the latest versions of the Lohit Indic fonts - so it's basically an updated and rebased version of aniruddha-adhikary's original pull request #1.
To make it clear exactly what is here, I've left the complete contents of the release tarball in each font's directory, although we'll only actually be using the binary .ttf files. We could strip out the readmes, changelogs, etc., if we don't want to clutter moztt with all that; I don't feel strongly about it one way or the other.