Add WithSkipEmptySourceMaps parser option

[dsmith3197]

The TypeScript compiler produces empty source map files for source files containing only type definitions.

This PR adds a WithSkipEmptySourceMaps parser option that ignores the empty source map error produced here.

[dop251]

I think the behaviour should be to simply ignore missing or invalid source maps. This will match nodejs and browsers.

[dsmith3197]

I think the behaviour should be to simply ignore missing or invalid source maps. This will match nodejs and browsers.

Are you suggesting that we remove the option altogether and always ignore empty/invalid source maps? Or are you saying that when the option is enabled, we should ignore all errors when parsing the source map?

[dop251]

The former. Both nodejs and the browsers seem to behave this way.