Add definitions for mustache.js 0.8.2

Add new definitions for 0.8.2, move 0.7 definitions and tests into
versioned files and remove empty .tscparams files.
Add parameter typing, fix old definition version

I was omitting the -noImplicitAny flag when testing; interestingly, even
the old (0.7.3) definitions failed the Travis CI tests...
Merge pull request #2862 from markashleybell/mustache-0.8.2

Add definitions for mustache.js 0.8.2