Allow searching meta fields by LIKE.

[bluehaoran]

Allow users to do a like search on meta values.

I couldn't figure out an elegant way to do this with Corcel as it currently is, so I added this for our own use.

My current use-cases are doing a case-insensitive search on posts by category, but I can also see wanting to retrieve by "category%".

Usage: you can now retrieve by meta, e.g.:

User::hasMeta(['first_name' => 'ADAM'])->get();
User::hasMeta(['full_name' => 'Adam%'])->get();

Added tests for this (hasMetaLike()) and hasMeta.

(Duplicates and supersedes #417.)

[jgrossi]

Hi @bluehaoran! first thanks for the PR! I pushed some changes just to improve tests readability and also avoid code duplication when creating scopeHasMetaLike() method, ok? take a look and let me know what you think of them, please. thanks! 😎💪

[jgrossi]

@bluehaoran also, can you add that to the README (documentation), please? thanks

[bluehaoran]

Hi @jgrossi, changes look fine! No objections. Updated the docs; hope you don't mind me using your name :)