Implement IDNA support for Lists

[c-mueller]

Resolves #28

Before passing processing URLs using the Ascii regex, they get passed through an IDNA decoder converting domains like mähl.de to 'xn--mhl-qla.de' making it conform to the regex and ready for blocking.

[codecov[bot]]

Codecov Report

Merging #29 into master will decrease coverage by 0.24%. The diff coverage is 57.14%.

@@            Coverage Diff             @@
##           master      #29      +/-   ##
==========================================
- Coverage   60.62%   60.38%   -0.25%     
==========================================
  Files           8        8              
  Lines         513      525      +12     
==========================================
+ Hits          311      317       +6     
- Misses        172      175       +3     
- Partials       30       33       +3

Impacted Files	Coverage Δ
list_map_handler.go	73.13% <50%> (-1.47%)	:arrow_down:
setup_parse.go	55.46% <60%> (-0.4%)	:arrow_down: