Fix python file2stringarray

[fmigneault]

Details

This update changes the internal operation accomplished by file2string_array process since it was attempting to create directly a CWL output of type File[].
To do that, it was actually hijacking the internal file cwl.output.json of cwltool by directly populating the contents of the expected output after process execution rather than letting the engine generate it, but format was invalid and still failing the execution anyway. The actual CWL content definition was defined as File, which did not match with the generated File[] pushed in cwl.output.json.

Multi-output (File[]) is also not yet supported in Weaver (see #25) because OGC API - Processes does not allow output multiplicity under a same output ID.

It as been decided that output should be adjusted to be a single File.
This better matches the original description of the process anyway, because old implementation was not even producing a JSON output file:

Transforms a file input into JSON file containing an array of file references as value.

Changes

• Modify problematic output location and execution methodology of file2string_array process so it does what
  it actually advertises in its abstract description and doesn't result in error after execution.

Fixes

• Fix invalid python reference in file2string_array process CWL definition (fixes [BUG] CWLTool throw error the missing folder for Python dist #275).
• Fix missing version field definition for file2string_array process and set it as 1.0.

[dbyrns]

Everything look good.