Restructure tests folder
Update Gruntfile

You can now run:
`grunt test:decoder` or `grunt test:encoder` to only run these tests.

The same goes for `grunt dev:decoder` and `grunt dev:encoder`
Reworked some tests
Merging new tests workflow branch
New tests
Merge remote-tracking branch 'upstream/master'

* upstream/master:
  New tests
  Reworked some tests
  Update Gruntfile
  Restructure tests folder