Feature/docker

[vincentmr]

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---

Context:
Some systems have messy environments which makes on-site deployment complicated. Docker is a solution to this issue.

Description of the Change:
Add Docker container utilities.

Benefits:
Easier deployment, visibility on DockerHub.

Possible Drawbacks:

Related GitHub Issues:

[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (17812fb) 99.13% compared to head (fcc5a32) 99.13%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #496   +/-   ##
=======================================
  Coverage   99.13%   99.13%           
=======================================
  Files         142      142           
  Lines       16798    16798           
=======================================
  Hits        16652    16652           
  Misses        146      146           

Files Changed	Coverage Δ
pennylane_lightning/core/_version.py	100.00% <100.00%> (ø)

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[AmintorDusko]

I had just a small suggestion, but overall looks pretty good!

[mlxd]

Some thoughts