Tweak completion text for generics

Do not include a leading space after "<of" because depending on the
user setting for how the completion text is selected we might end
up with a double space, like "<of  ", when the entry is selected.
Improve semantics for code completion

* Prefer bound ASTs over unbound, even if the unbound AST is newer

* Do not trigger completion on space, tab, or equals characters

* Do not include [ or ( in the trigger word length

* Regarding text preceeding the completion character, treat = and == the
  same
Fix bug with code completion and empty doc string
Previous commit did not actually fix bug. This time...
Update status of manual tests
Bugfix for the way regions are extended

Resolves issue #26
Update status of manual tests