Prepare 1.3.0 release

[arturbosch]

This release sets the minimum supported Gradle version to 5.
1.2.2 was released to support gradle 4.9+ for the last time and include the Project.detekt deprecation warning.

[codecov-io]

Codecov Report

Merging #2165 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master    #2165   +/-   ##
=========================================
  Coverage     81.12%   81.12%           
  Complexity     2055     2055           
=========================================
  Files           339      339           
  Lines          5874     5874           
  Branches       1070     1070           
=========================================
  Hits           4765     4765           
  Misses          536      536           
  Partials        573      573

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[schalkms]

I merged two additional PRs, because I forgot about your PR that releases v1.3.0.
Can you please update the changelog once more?
Sorry for that! @arturbosch

[arturbosch]

@schalkms no problem, I was kinda busy, so I will see what else we can/will ship with 1.3 :)