Merge pull request #584 from am11/master

Code: More analysis warning fixes
Adds functionality for set-nth.

Fixes #578 and #581.
Fixes clang warning (should also fix #586)
Radically simply the map parsing logic
Allow map keys to be function calls

The majority of changes in this diff is simple moving Arguments and
Argument above Function_Call in the source order.
Merge pull request #596 from xzyfer/feat/map-parser-electic-boogaloo

Radically simply the map parser logic
Merge pull request #597 from xzyfer/feat/functions-as-map-keys

Allow map keys to be function calls
Add support for interpolated strings as map keys
Merge pull request #598 from xzyfer/feat/interop-as-map-key

Add support for interpolated strings as map keys
SourceMap: Don't entertain garbage data. (#586)