Create unified CLI for file actions

For common file operations the existing scripts should be merged into a unified one (e.g. repod-file). It should provide:

• db2json (functionality)
• json2db (functionality)
• introspection into package metadata by returning all or selected components of a consumed package (e.g. Package, .MTREE, .BUILDINFO, .PKGINFO representation in JSON)
• transformation of package data into management repo representation
  • create model for package consumption and representation !57 (merged)
  • add creation from Package to OutputPackageBase