minor changes
* use ANTLR icon for files
* remove comments from text when the mouse is over
handle '/' char inside actions gracefully, fix #2
fix #1 wrong package under windows
deprecated gated predicate usage, fix #4
rename Runs As > ANTLR 4 to Generate ANTLR Recognizer and move option to the External Tools menu, fix #6
improve folding and collapse options, actions and comment by default, fix #7
follow -o option when the user say it, fix #5
print ANTLR version when building, fix #8
* validate ANTLR jar
* show tips when a bad JAR is found
code completion for grammar options, fix #9
Validate and highlight 'Rule Element Options' fix #10
Improve highlight for target action, fix #11
* cache ANTLR version
* make ToolRunner injectable by Guice