Intial file created for TypeScript

Not all content but it's a good start
Some re-phrasing and typos
Tutorial on classes and functions added

TODO: more on indexers, check the comment emitted twice for f2 function
Added inheritance and overwrite examples
Small typos
Added section on Modules

Indented comments and edited the Interfaces part. Still missing indexers and Generics.
Added filename in header
Merge remote-tracking branch 'upstream/master'
Generics added

And a few typos corrected, ready for pull request
Merge remote-tracking branch 'upstream/master'
Fixed errors and typos

After review from from Nami-Doc
Merge pull request #739 from Pvlerick/master

TypeScript page created