added prettier with husky

[Shinigami92]

• Check the commit's or even all commits' message styles matches our requested structure.
• Check your code additions will fail neither code linting checks nor unit test.

Short description of what this resolves:

The whole code is pretty formatted
This happens when a contributor commits a file
husky will register an precommit event and perform pretty-quick, which will format the submitted files with prettier and print a helpful message to the console/terminal

I oriented myself to https://github.com/palantir/tslint/pull/4012/files

Used tools:

• https://prettier.io
• https://github.com/azz/pretty-quick#readme
• https://github.com/typicode/husky/tree/v0.14.3

Proposed changes:

• Formatting with prettier at commit

[codecov-io]

Codecov Report

Merging #255 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##           master   #255   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           1      1           
  Lines           1      1           
=====================================
  Hits            1      1

---

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[Shinigami92]

The configuration of

{
    "printWidth": 100,
    "singleQuote": true
}

is arguable.

printWidth 100 because on a 1080p monitor in the GitHub Web GUI you have no wraps in the side by side view
singleQuote true because the current style (and also my preference) uses this

but we can choose a complete other config if you want

[thedaviddias]

Solved with #287