Adds missing unit tests, end to end testing of the daily/monthly CLI and some code cleanups

[stijnvanhoey]

@peterdesmet to support the 'all' option, one can use the 0 option (to keep it an integer)

❯ vph5_to_vpts --help
Usage: vph5_to_vpts [OPTIONS]

  Convert and aggregate h5 vp files to daily/monthly vpts files on s3 bucket

  Check the latest modified h5 files on the s3 bucket using an s3 inventory,
  convert all ODIM hdf5 profiles files for the days with modified files to the
  vpts-csv standard and upload the vpts-csv daily/monthly files to s3.

Options:
  --modified-days-ago INTEGER  All bucket files with a modified date between
                               now and N modified_days_ago will be taken into
                               account for the recreation of daily/monthly
                               files. If 0,all nucket files will be taken into
                               account for the recreation.
  --aws-profile TEXT           Optionally, define the AWS profile used to run
                               the command for interaction with the AWS s3
                               bucket.
  --help                       Show this message and exit.

With This PR, the targeted set of functionalities is provided. I marked as draft as I do have to fix an issue with the sphinx documentation building. I'll do that asap.

[coveralls]

Pull Request Test Coverage Report for Build 4561907488

• 58 of 59 (98.31%) changed or added relevant lines in 6 files are covered.
• 7 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+36.7%) to 88.018%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/vptstools/bin/vph5_to_vpts.py	16	17	94.12%

Files with Coverage Reduction	New Missed Lines	%
src/vptstools/vpts_csv.py	7	76.99%

Totals
Change from base Build 4409840957:	36.7%
Covered Lines:	392
Relevant Lines:	412

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💛 - Coveralls

[peterdesmet]

Sounds good, nice coverage!

please correct typos to:

All bucket files with a modified date between now and N modified-days-ago will be taken into account for the recreation of daily/monthly files. If 0, all bucket files will be taken into account for the recreation.

[peterdesmet]

@stijnvanhoey I made some changes to this in a separate PR #37, so you can review those better.