Case insensitive keywords

[subeax]

Hi!
Thank you for this amazing library!

I think it may be helpful to ignore keywords case.

const options = {
    keywords: ['name', 'town'],
};

const query = "Name:John,Ben,Bill";

might be done by adding new option, like

ignoreCase: true // or something else

and adding condition to line 130:

// We got an advanced search syntax
else {
 key = options.ignoreCase 
          ? term.keyword.toLowerCase() 
          :  term.keyword
...

Thoughts? :)

[nepsilon]

Yes, very good idea! Can you send a pull request with this addition and a few tests?