Add ability to ignore / exclude globs

[schoblaska]

This gem has an unowned_globs config option, which acts as a "TODO" list for code that has not yet been assigned an owner. However, there is currently no way to ignore files / globs from code ownership entirely.

Example: A team owns a directory, but it contains a nested file that is autogenerated and changes frequently.

team_code
 ∟/src
   ∟/generated/__some_file__
 ∟/config

Example: js_package_paths causing node_modules or other nested package.json files to be parsed

• Have way to disable Javascript Package Ownership #76

In this case, an ignore / exclude rule would potentially prevent these package.json files from being parsed. So, this feature might control which files are owned, but also which files are parsed as configuration for code_ownership.