Implement top level API

[phated]

Thinking out loud...

This will (likely) be a stream that parsers a sourceMappingURL comment from a file and passes it to a mapFn. If undefined or null is returned from mapFn, the comment should be removed from the original content. If a value is returned and is different from the original comment, it should replace the original comment (comparing original and new reduces the work done). If values are the same, ignore and pass the file on.

[phated]

The mapFn syntax should be mapFn(sourceMappingURL, file)

[phated]

This replaces the sourceMappingURL option in gulp-sourcemaps

[phated]

Empty string might remove along with undefined and null. Not sure yet

[phated]

Initial impl thoughts at 1dd6b48