Write Status file in WALA Lib folder and other nits

[vrdmr]

Description

Adding a status file, which gets updated whenever a new status file is uploaded. It contains relevant information required for debugging and troubleshooting.

other nit fixes. No new tests added as this is heavily tested in the test_extensions.py class.

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[boumenot]

Please add a test case(s).

[jasonzio]

I can't see who calls write_ext_handlers_status_to_info_file(), but the code itself looks okay.

[narrieta]

LGTM

[vrdmr]

Thank @narrieta @boumenot