detect spelling errors in keyword in wylie

[berger-n]

@JannTibetan following the recent issue with a user mixing Wylie and English

• I've added @eroux 's spellchecker for Tibetan (link) to the keyword search UI when Wylie is selected
• I've also added another bullet in the list when getting no result in Wylie:

you can test it here: https://library-dev.bdrc.io/

note sure where to go from there:

• the spellchecker is for Tibetan in Unicode so we convert text from Wylie to use it in the process it sometimes modify it (adding vowels like th --> tha or bl --> bla) thus some spelling errors are not detected + it's not straightforward to tell the user where exactly his error is
• the link to the results in English seemed a good idea in this example but testing a bit more it appears it can lead the user to think what he's looking for isn't available in our data though it is if he does the right search in Wylie or Tibetan instead! compare results for "ta la'i bla ma 09"@bo-x-ewts and for "9th dalai lama"@en
  or even "9th dalai lama AND biography"@en which has a lot less results that "lung rtogs rgya mtsho AND rnam thar"@bo-x-ewts
• so maybe it would be better to replace it by a polite "do not mix English terms and Extended Wylie"

[eroux]

I think it's pretty good but I wonder if there's a way to unerline the errors and not force two clicks? there are always strange cases where it's normal to input Tibetan that is incorrect according to the spellchecker (like Sanskrit names), we don't want to penalize that too heavily