Add a function to force color in console output

[orobardet]

Add a function ForceConsoleColor, like DisableConsoleColor but to force coloring the output.

It usefull when some IDE's integrated console (like IntelliJ or Goland) are not detected as TTY, but can display colors.

Also helps if one want to output color in log file (#1590) and as a workaround for #1547.

[codecov]

Codecov Report

Merging #1724 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1724      +/-   ##
==========================================
+ Coverage   98.48%   98.48%   +<.01%     
==========================================
  Files          41       41              
  Lines        2044     2046       +2     
==========================================
+ Hits         2013     2015       +2     
  Misses         19       19              
  Partials       12       12

Impacted Files	Coverage Δ
logger.go	100% <100%> (ø)	⬆️

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[thinkerou]

@orobardet how to use it? and what distinguish it from disableColor?

[orobardet]

@orobardet how to use it? and what distinguish it from disableColor?

I added a new section in the README about controlling the colorization of log outputs, including the existing DisableConsoleColor and the new ForceConsoleColor.