Fix Transliteration Helper Interaction

[SebastinSanty]

Currently, the transliteration helping mechanism takes the english input and then retrieves the appropriate transliteration and shows to the user. However, there are interaction flaws with this:

• Showing up of English characters in the translation box, which overlaps with the hindi suggestion.

• Issues for users of Language Keyboards as even with that input, the transliterator calls the API. This can be fixed by limiting call to transliteration API only if the input unicode lies in the range of English (Latin) script.