fast-scan: Apply performance improvements to code: batch 2 (file system walking or from benchmark results)

[pombredanne]

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

Edit: We are addressing performance issues in package scan (package assembly steps) which have known performance issues.

[AyanSinhaMahapatra]

This is completed with:

• Improve package scan performance #4606
• Update scancode-toolkit with faster package scan scancode.io#2000

The package scan performance improvements were:

• Skipping binary package detection steps by default, and introducing a new CLI option --package-in-compiled to detect packages in compiled binaries like rust/go binaries
• creating cached regex patterns and multiregex pre-matchers, for a fast package path detection filtering step
• make --package-only scans faster by skipping license cache loading
• make changes in scancode.io to support the same performance improvements there: