Save_data methods

[StijnKas]

This PR adds save_data() methods to both ADMDatamart & ValueFinder, using the newly added cache_to_file() method in cdh_utils. It also adds the default caching filenames to cdh_utils, so it will recognize it as the latest file when it conflicts with others.

[codecov]

Codecov Report

Base: 78.14% // Head: 77.62% // Decreases project coverage by -0.51% ⚠️

Coverage data is based on head (03ce6be) compared to base (4f40e9d).
Patch coverage: 40.74% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #61      +/-   ##
==========================================
- Coverage   78.14%   77.62%   -0.52%     
==========================================
  Files          14       14              
  Lines        2237     2257      +20     
==========================================
+ Hits         1748     1752       +4     
- Misses        489      505      +16     

Impacted Files	Coverage Δ
python/pdstools/adm/ADMDatamart.py	91.00% <22.22%> (-1.70%)	⬇️
python/pdstools/valuefinder/ValueFinder.py	91.57% <33.33%> (-1.90%)	⬇️
python/pdstools/utils/cdh_utils.py	85.63% <58.33%> (-2.47%)	⬇️

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

☔ View full report at Codecov.
📢 Do you have feedback about the report comment? Let us know in this issue.