Add DeprecationWarnings to several old functions

[freemansw1]

This PR is simply to add several DeprecationWarnings to various functions that have been discussed before as needing to be removed or substantially reworked for v2.0. Getting these DeprecationWarnings into v1.5 should give users enough time to migrate away from the functions.

Resolves #198 and #158.

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[codecov]

Codecov Report

Base: 35.06% // Head: 34.89% // Decreases project coverage by -0.17% ⚠️

Coverage data is based on head (44b9dd5) compared to base (dfe3b38).
Patch coverage: 12.50% of modified lines in pull request are covered.

Additional details and impacted files

@@              Coverage Diff              @@
##           RC_v1.5.0     #200      +/-   ##
=============================================
- Coverage      35.06%   34.89%   -0.18%     
=============================================
  Files             10       10              
  Lines           2099     2115      +16     
=============================================
+ Hits             736      738       +2     
- Misses          1363     1377      +14     

Flag	Coverage Δ
unittests	34.89% <12.50%> (-0.18%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
tobac/plotting.py	3.05% <0.00%> (-0.04%)	⬇️
tobac/centerofgravity.py	7.05% <20.00%> (+0.80%)	⬆️
tobac/wrapper.py	8.06% <33.33%> (+1.28%)	⬆️

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[snilsn]

Nice work @freemansw1. After my experience with these functions I think that this step is the right way to go.

[JuliaKukulies]

Perfect, that makes sense @freemansw1. Thanks for your changes! Is there any clever way we can go about the coverage in pull requests like this or are we just ignoring it because we know we only added warnings?

[freemansw1]

@JuliaKukulies we have changed the code coverage threshold to -1% in #183, but I don't know that those changes have been merged back into v1.5.0 yet.

[freemansw1]

Thanks for the quick reviews!

[JuliaKukulies]

@JuliaKukulies we have changed the code coverage threshold to -1% in #183, but I don't know that those changes have been merged back into v1.5.0 yet.

Right, sorry! I was aware of the change with #183 but misread and thought this would be even more than -1 %. There are probably a few things that haven't merged back yet, but I guess this will be done directly after the release so never mind

[freemansw1]

Yeah, now that we're so close to 1.4.0, I'm planning to wait to merge 1.4.0 into 1.5.0 until release.