Updated grunt declarations to match 0.4.x documentation.
Had to weaken some return types for TypeScript (left comments).

Conflicts:
	gruntjs/gruntjs.d.ts
Updated for contribution guidelines.

Conflicts:
	README.md
Switched to generic MultiTask for structured configuration.
Added Template and Util modules.
Fixed implicitAny bugs.
Merge pull request #1195 from jeffmay/grunt-ts-defs

[master] Updated grunt declarations to match 0.4.x documentation.