Add support for including file path for collation

[rhyshort]

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What

Add support for including file path for collated files, this solves the problem where if you are collecting files from multiple agents, file path clashes occur. Adding the --include-file-path option will ensure that the file names are unique

Why

When harvesting evidence collected via auditree-framework's agent mode across multiple agents in a single collate run evidence gets overwritten. This means when collecting the same evidence file from multiple agents has to be achieved with a multiple runs rather than taking advantage of the feature to collect multiple files at once.

How

• add option --include-file-path to accepted arguments, when set to true evidence located at raw/foo/foo.json would be collated as 20191106_raw_foo_foo.json

Test

• Added test for new cli argument (test_collate_include_file_path)
• Added test to verify file path is added to collated file name (test_write_includes_file_path)

Context

[cletomartin]

Thanks @rhyshort! +1

[rhyshort]

@cletomartin Great thanks. Could you merge then please? I don't have commit rights :)