Output of the CLI parser is incomplete

[armintaenzertng]

When using the CLI parser to read in and print out SPDX documents, multiple fields are missing (like license comments or multiple checksums) and others are printed out even though they contain no info (like attribution texts or annotations). This should be further investigated and then updated to include all available information in the output (and nothing more).

[meretp]

Additionally the parser fails if a document contains no package, this output needs to be optional as packages are optional.

[armintaenzertng]

The new refactored version uses tag-value for output to stdout, thus this error is fixed.