Features/469 kmeans rework

[Cdebus]

Description

Implementation of cdist function in heat/spatial/distances.py module for accelerated distance matrix computation
Rework of kmeans to speed up computation

Issue/s resolved: #467 and #469

Changes proposed:

• Module spatial/distances with function cdist
• heat.cdist works with either torch.cdist or via quadratic expansion (experimental!)
• Kmeans uses cdist in kmeans++ initialization and Lloyed iterations
• removed dimension expansion to 3D in kmeans (redundant)
• still requires proper documentation

Type of change

• Optimization

Due Diligence

• All split configurations tested
• Multiple dtypes tested in relavent functions
• Documentation updated (if needed)
• Updated changelog.md under the title "Pending Additions"

Does this change modify the behaviour of other functions? If so, which?

no

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@9d9ebba). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master     #470   +/-   ##
=========================================
  Coverage          ?   96.71%           
=========================================
  Files             ?       60           
  Lines             ?    12255           
  Branches          ?        0           
=========================================
  Hits              ?    11853           
  Misses            ?      402           
  Partials          ?        0

Impacted Files	Coverage Δ
heat/cluster/kmeans.py	82.22% <ø> (ø)
heat/cluster/tests/test_kmeans.py	84.37% <100%> (ø)
heat/spatial/tests/test_distances.py	90.19% <100%> (ø)
heat/spatial/distances.py	100% <100%> (ø)

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[coquelin77]

can you please update the changelog?