Feature: Exclude source maps by pattern.

[ryan-roemer]

The source map inclusion feature can include discovered source maps in node_modules. Typically, we would only want our application source maps.

Task:

• Add a filter on source maps to only include (and include misses) for things matching a pattern so you can e.g., just do source map inclusion for application source files and not things in node_modules.
• OR do something like add a glob/pattern matcher for files that is separate and just a pattern matcher so that you can exclude any type of files and then we could add that for like !**/node_modules/**/*.js.map as an implementation of Feature: Glob patterns to affect package.<PKG_NAME>.trace #21