fast-scan: Apply performance improvements to code: batch 1 (copyright or from benchmark results)

[pombredanne]

This is to apply some performance improvements to code either for copyright or otherwise from benchmark results.

[JonoYang]

The pygmars library performed a lot of regex substitutions unnecessary for scancode-toolkit's use:

• A lot of time is spent in re.sub when calling ParseString.__str__ pygmars#13

... so I have removed it in:

• Do not format in ParseString.__str__ #13 pygmars#14

... and created a new release of pygmars v1.0.0

I then updated pygmars in scancode-toolkit in:

• Update pygmars #4477