cli: multiple filters in get-metadata command

[joudmas]

closes #136

Adds new metadater file for metadata utilities Adds support for multiple filters

[codecov[bot]]

Codecov Report

Merging #137 (ea24900) into master (40a3b3b) will increase coverage by 0.97%. The diff coverage is 92.85%.

Additional details and impacted files

[](https://app.codecov.io/gh/cernopendata/cernopendata-client/pull/137?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cernopendata) ```diff @@ Coverage Diff @@ ## master #137 +/- ## ========================================== + Coverage 79.71% 80.68% +0.97% ========================================== Files 11 12 +1 Lines 700 730 +30 ========================================== + Hits 558 589 +31 + Misses 142 141 -1 ``` | [Files](https://app.codecov.io/gh/cernopendata/cernopendata-client/pull/137?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cernopendata) | Coverage Δ | | |---|---|---| | [cernopendata\_client/cli.py](https://app.codecov.io/gh/cernopendata/cernopendata-client/pull/137?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cernopendata#diff-Y2Vybm9wZW5kYXRhX2NsaWVudC9jbGkucHk=) | `92.81% <90.00%> (+1.44%)` | :arrow_up: | | [cernopendata\_client/metadater.py](https://app.codecov.io/gh/cernopendata/cernopendata-client/pull/137?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cernopendata#diff-Y2Vybm9wZW5kYXRhX2NsaWVudC9tZXRhZGF0ZXIucHk=) | `93.47% <93.47%> (ø)` | |