Added 'dynamic' type keyword to syntax highlighting
Removed upper case 'Dynamic' keyword in Regex
Removed upper case 'Dynamic' keyword 

Removed upper case 'Dynamic' keyword in JSON language file
Removed Dart.JSON-tmLanguage file.

It's obsolete and we are switching to editing using YAML syntax.
Removed all instances of 'Dynamic' keyword.

Converted the tmLanguage to YAML, edited the YAML file and then
converted back to tmLanguage using AAAPackageDev.
Merge pull request #115 from austincummings/master

Added 'dynamic' type keyword to syntax highlighting