Create an ACE editor mode for Jason

[cleberjamaral]

We are currently using erlang mode but there are several tokens that are not suitable, for instance, the #comment one. It is also necessary to create many others like for adding and removing beliefs, for plans, namespaces and so on.

Some material about how to create/extend a mode:
https://github.com/ajaxorg/ace/wiki/Creating-or-Extending-an-Edit-Mode
For testing highlighting script
https://ace.c9.io/tool/mode_creator.html
For testing regex:
https://regex101.com/

[cleberjamaral]

We now have a grammar completely based on erlang one. At the current time, the only improvement is that it is correctly accepting comments in jason using double slash and block comments using /* */. The grammar now needs a big revision because many erlang tokens are not suitable in jason context and many jason tokens that are not covered.