Overhaul, I hope it works well

Hi. If anyone uses this then be advised that I just overhauled the whole code. It does far less allocations now and there were even some bugs in the parser. Should be fine now. I have run some tests (see test.c), and it seems fine, so this is v1.0rc for a while I guess.

The code uses some C11 features, but all newer compilers should handle them well, they might throw a warning or two at you though.

As usual, the best way to use this is to simply add jzon.c and jzon.h to your project and call jzon_parse(your_string_with_jzon) (you have to read the file yourself!)