Add basic mapping to map few columns of given CSV format to json.
Implement algorithm to use mapping file as template to convert CSV rows to release-objects in the JSON result.

- metadata about the CSV can be given via CLI args
- each line of the CSV will be converted into a 'release' according to the given schema
-m Update README
-m Re-use complete schema structure, not only the part for releases.
Merge pull request #1 from florianpilz/master

Basic Implementation