Update release procedure

[hndgzkn]

• Updates switcher.json with new release version.
• Updates RELEASE.md to add Before release section.

[codecov-commenter]

Codecov Report

Merging #92 (f49ff0a) into master (9781d2a) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #92   +/-   ##
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  Coverage   82.41%   82.41%           
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  Files          24       24           
  Lines        2228     2228           
=======================================
  Hits         1836     1836           
  Misses        392      392           

[hndgzkn]

Shall we think of a more detailed release procedure (create release branch, keep a changelog file, etc)?

[tomMoral]

LGTM! If you see any valuable steps to detail, feel free to add them but it is already good enough I think