Add Indonesia Language

[dhi9]

No description provided.

[codecov]

Codecov Report

Merging #64 (193357e) into master (e8f901c) will decrease coverage by 1.48%.
The diff coverage is 33.33%.

❗ Current head 193357e differs from pull request most recent head 2a98c14. Consider uploading reports for the commit 2a98c14 to get more accurate results

@@             Coverage Diff             @@
##            master      #64      +/-   ##
===========================================
- Coverage   100.00%   98.51%   -1.49%     
===========================================
  Files            2        2              
  Lines          132      135       +3     
===========================================
+ Hits           132      133       +1     
- Misses           0        2       +2     

Impacted Files	Coverage Δ
slug.go	98.18% <0.00%> (-1.82%)	⬇️
languages_substitution.go	100.00% <100.00%> (ø)

[matrixik]

I added idn and ind for Indonesian language that are specified in ISO 3166-1 and ISO 639-1 and simple test.

Thank you for this change.