Add operators for case-insensitive equal checks

[Andre601]

Adds operators for case-insensitive equals checks (Including negated ones)

• ~== and ~= can be used for equalsIgnoreCase check
• !~ can be used for negated equalsIgnoreCase check

I did ~== as the equivalent to ==, tho I think ~= for it is better and just ~ for =?

[Andre601]

I decided to switch the operands to =~ and ~ to keep them similar in length and design to ther counterparts == and = respectively.

Was thinking of doing ~~ but that feels a bit too ambigous, as nothing would hint at equality check here.

[CodeCrafter47]

I didn't realize this has been sitting here for 3 weeks. Sorry for the delay.