CPU Update [38 new instructions] (#9)

* added 12 new operations (INC and DEC) without testing

* added AND operation and test for INC zero page

* modified writeAbsoluteX, added tests for INC, cargo fmt

* added tests for all INC and DEC ops

* added tests for all AND addressing modes

* improved test clarity, added tests for some LDA ops, removed some repetetive code

* further removal of repetitions, added rest of LDA ops and unit tests for LDA

* added LDX op, added zero_page_y addr mode

* added LDY op with unit tests

* fmt

* added cpu folder, fixed absolute_write_x