Reorganize files

* Move non-ST-commands under lib
* Use simple modules if possible
* Change import paths as needed

--HG--
rename : sublimetext/FSharp/fsac/server.py => sublimetext/FSharp/lib/fsac/server.py
First implementation of symbol help text
Use helper functions
Merge pull request #398 from guillermooo/st-refactor

ST refactor
update help output
Improve tooltip command
First implementation of completions functionality
Merge pull request #400 from guillermooo/st-next

Basic autocomplete implementation; fix tooltip functionality
Add tests
Fix test
Merge pull request #401 from guillermooo/st-tests

Add tests for helpers