Implement a linter/checker

[akshdeep-singh]

Summary

The user input can be anything. Invalid Unicode sequences can result in unexpected results from gurmukhi-utils functions. So, a linter/checker is required to extract/show various kinds of invalid/unsupported character sequences in the Gurmukhi text.

It is better to separate the linter from other functions.

Related: #210

Some Examples of invalid/unsupported character sequences:

• Invalid sequence of diacritics
• Invalid combination of diacritics (Example: Valid combination of dual matras)
• Diacritics without base letter
• Invalid Consonants after Virama
• Non-normalized Gurmukhi text
• Unicode text mixed with Ascii
• Spelling mistakes (Valid sequence but meaningless word)
• Grammatical errors (Sentence formed from the sequence of words is meaningless)

Approach