Allow configuration to define SimplePatternBasedLicense instances

The concept here is to rework the license matching definitions so that the SimplePatternBasedLicense can be instantiated from a configuration file.

The reasoning is that there are a number of licences that are of particular interest in projects both inside and outside of the ASF that are not currently included in the code.  This change will allow users to define the string matching for any license that can be matched by simple string matching.

The proposal is to move all the static definitions into a default file and allow the default to be ignored/overridden.

Command Line Flags

Add a flag --no-default-file to skip reading the default definitions from within the package.

Add a flag --definition-file that accepts a file name argument, reads it and adds the definitions to the list of definitions that are checked.  Ensure that multiple --definition-file arguments may provided and that they are added in the order in the --definition-file.

Static definition changes

• Modify Meta.Data so that the license family category values are not statically defined.
• Modify Meta.Data so that the license family names are not statically defined.

see https://github.com/apache/creadur-rat/pull/157 for details