[Lock] add safeguards for network/distributed file systems

[johntruckenbrodt]

• wait some time for the target's parent directory to exist
• if soft=True, wait for the target to exist
• retry creating lock files for some time
• all methods respect the user-defined timeout

[coveralls]

Pull Request Test Coverage Report for Build 21959499660

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 33 of 39 (84.62%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 55.008%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pyroSAR/ancillary.py	33	39	84.62%

Totals
Change from base Build 21956936674:	0.1%
Covered Lines:	4163
Relevant Lines:	7568

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💛 - Coveralls