This commit fixes the following behaviors:
Indirect X zero page addressing should always wrap and stay on zero page
BRK should disable interrupts
ADC in decimal mode should carry between nibbles based on adjusted,
not original values.
Writes of status register to the stack should always set M and should
set B on BRK/PHP and ~B on IRQ/NMI
Found and tested against
https://github.com/Klaus2m5/6502_65C02_functional_tests/blob/master/6502_functional_test.a65