Remove some out-of-date restrictions and clarify some wording.
Add glossary for Numba
Fix typo and add link to glossary.
Add glossary links for nopython and object mode
Merge pull request #804 from seibert/array_doc

Remove some out-of-date restrictions and clarify some wording.
Merge branch 'master' of github.com:numba/numba into pickle_dispatcher