Running jas scanners in parallel

[orz25]

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In this PR we worked on running all scans (sca, jas) in parallel, using gofrog parallel package .

The part of building the dependency tree is not running in parallel, the command will first build the dependency tree to all modules, and then scan them

We added a new flag for the audit command, "threads", allowing the user to input the number of parallel tasks that can be created during the run.
The progress bar changed - it will show 2 statuses: Calculating {tech} dependencies, Scanning for issues.

PR for needed changes is Frogbot - jfrog/frogbot#692
PR for updating audit command document - jfrog/documentation#134