Add pt-BR spell checker

[rodcorsi]

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Summary
Upgrade simple-spellchecker and add entry in menu to support pt-BR spell-checker

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[yuya-oc]

Thanks @rodcorsi! Looks good to me.

Just curious, how did you prepare the word list to create the dictionary file in jfmdev/simple-spellchecker#12?

[rodcorsi]

I got this file from github.com/erdavila/M-Tree and normalize it using the simple-spellchecker cli

[yuya-oc]

Thanks for information.

[jasonblais]

@rodcorsi You're awesome. Thank you so much for this great contribution 🎉