add font, style for "lang-font" class | remove "int-he" and "int-en" class (React component)

[lobsam]

Problem defination:

Font stying for language Tibetan is handled by class='int-he' and for English by class="int-en". but there is no class for other languages that handles the font styling. We need common class that handles and solved this issue.

Implementation steps to solves :

• removeint-heand int-en class
• add className = ''lang-font' that handles font stying for every languages