`OptTable` was a source of consistent churn due to new arguments to the
`OPTION` macro. LLVM 3f092f37b7362447cbb13f5502dae4bdd5762afd extracted
the handling of the common option parts (eg. an ID and an info) out into
separate macros to reduce this - use those here (since unsurprisingly,
more arguments were added).
Changes:
* Terminate all namespaces with the correct closing comment.
* Make sure argument names in comments match the corresponding parameter name.
* Remove redundant get() calls on smart pointers.
* Prefer using "override" or "final" instead of "virtual". Remove "virtual" where appropriate.
The options themselves are now in swift::options (from swift::driver::options).
The soon-to-be-renamed createDriverOptTable() is now directly in the swift namespace.
Swift SVN r19825
This allows swiftFrontend to drop its dependency on swiftDriver, and could
someday allow us to move the integrated frontend's option parsing out of
swiftFrontend (which would allow other tools which use swiftFrontend to
exclude the option table entirely).
Swift SVN r19824
