TISTUD-4173:JS Content Assist: access operator closes content assist menu

The following changes were made 

1. Activate the trigger character "." in Java script content assist 
2. Accord highest relevance to exact matches so that sorting places them on top.
3. Change proposal name sorting to ascending alphabetical order .. eg: foo,fooa,Fooa,Foo will be sorted to foo,Foo,fooa,Fooa when CA is triggered through ctrl+space
4.Modified tests to reflect new sorting