Allow exclude patterns to be read from a file or files

Context

The apache-rat-plugin ignores by default the .gitignore files. However, for every file/pattern added to those files, an explicit exclusion must be set in the plugin's configuration.
Given that git-ignored files won't be uploaded to the SCM and shouldn't be part of a release, it would be nice that the apache-rat-plugin automatically considered those git-ignored files as implicit exclusions.

Implemented for

Currently implemented for the following soure code management systems:

• SVN
• Git
• Bazaar
• Mercurial and
• CVS.

The solution just takes each line of the ignore file as an exclusion that is not a comment line.
Thus no special logics for exclusions are parsed or different functionalities of a SCM taken into account.
Each line is taken as it is and added to RAT's default exclusions.

Example usage

You can configure parsing SCM ignore files by a environment variable

mvn -U -debug -Drat.parseSCMIgnoresAsExcludes=true

or in your configuration section of apache-rat-maven plugin

<parseSCMIgnoresAsExcludes>true</parseSCMIgnoresAsExcludes>

This features is enabled by default.

In case you want to speed up the build you may disable it and set it to

false

.