Move TH1IntegrateWithPartialBins from C++ to Python

[heijligen]

ROOT.HDTV.TH1IntegrateWithPartialBins() is only used in histogram.py.
Since it is a small and easy function, it can be implemented directly in PyROOT and does not need to be compiled.

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This patch isn't covered by the test suite. I'm also unsure how to trigger the function manually. Manual tested (#52 (comment))

[codecov]

Codecov Report

❌ Patch coverage is 25.00000% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 62.80%. Comparing base (4374fa9) to head (262d3b3).
⚠️ Report is 33 commits behind head on master.

Files with missing lines	Patch %	Lines
src/hdtv/histogram.py	25.00%	9 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #52      +/-   ##
==========================================
- Coverage   63.07%   62.80%   -0.28%     
==========================================
  Files          70       69       -1     
  Lines       10066     9880     -186     
==========================================
- Hits         6349     6205     -144     
+ Misses       3717     3675      -42     

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[heijligen]

I've found the trace from the shell to the modified function
The new function is used in Histogram.Plus (src/hdtv/histogram.py), which is called from SpecInterface.SpectrumAdd (src/hdtv/plugins/specInterface.py), which get added to the cli via TvSpecInterface(same file asSpecInterface) as spectrum add` command.

I've done the following A/B test to see if the modification produces a different result.

hdtv> spectrum get o.mtx
hdtv> spectrum get o.tmtx
hdtv> spectrum add 0 1
hdtv> spectrum write o_add_test.mtx lc

now adding this patch and redoing the steps 1 .. 3. The 4th step is

hdtv> spectrum write p_add_test.mtx lc

So we have o_add_test.mtx as original spectrum without the patch and p_add_test.mtx as spectrum with this patch applied.

Both have the same md5 hash

bae3e49510f567e65f52f12cd55dc3b7  o.mtx
55f0b439b5704e6db910f6b4c3ef9aff  o.tmtx
c762f5f7cf7352a1ab965a203ddc9c40  o_add_test.mtx
c762f5f7cf7352a1ab965a203ddc9c40  p_add_test.mtx