[BROOKLYN-166] Replace existing textareas for editing YAML with Composer Tab + Codemirror

[m4rkmckenna]

Continuatiion of work started in apache/incubator-brooklyn#865 by @azbarcea for BROOKLYN-166

[ahgittin]

i think this is an accidental reversion. the version numbers should be included. (you might want also to auto-regen the license file -- that also has some wanted new stuff removed but it's not a big deal.)

[ahgittin]

i've done the dull part, tomorrow i'll do the fun part, trying it out. thanks @m4rkmckenna @azbarcea!

[m4rkmckenna]

@ahgittin This PR does not address autocomplete ... thought it better to get the basic functionality in fist

Example of basic auto complete HERE

[ahgittin]

Nice work @m4rkmckenna @azbarcea . Merged (and combined all the license items as "codemirror" with a list of files.)

It looks like we now have all the old functionality. A few things I think still need work:

Important:

• Composer should indicate whether I'm adding to catalog or deploying
• In wizard popup:
  • need a way to get to composer when not selecting a catalog item, ie writing new yaml (common user workflow)
  • "preview" button is not working; it could instead become "Open in Composer"
  • probably no need for the tabs?

Nice to have:

• In composer, blueprint-to-deploy mode could have an option "open as catalog item"
• In catalog, could have "Edit" mode for blueprints that have associated yaml (would be easy and very nice i think!)

Probably not worth it:

• In composer, if in catalog mode, with a single item, we could have an "open as blueprint" mode

[ahgittin]

One more important item:

• The dialog should track whether it is a catalog item or a blueprint. Otherwise someone might deploy when they intended to add to the catalog!

[ahgittin]

(This will help prevent autodetect mode problems, which happen for instance if you have a comment on a line before a brooklyn.catalog: line!)

[ahgittin]

Changes are done in #5 and #7