More accurate delay
Accurate on 1 microsecond.
Fairly accurate

Decviates on 0-200 ns up to 10 microseconds.
Changed pwm_channel_disable() and made it block till the channel has
been disabled.
Small changes in PIO
Added pwm_set_clkx in pwm.c
Updated the test-file

Now contains accurate test function.
As accurate as it gets
Removed code that was commented away in delay.c
Bugfixed pwm_set_channel_frequency() in pwm.c
+ Created new function, pwm_init_peripheral(), and finished
pwm_init_channel() in pwm.c.
+ Made bugfix in pwm_turn_off_clkx().
+ Commented on the code.
Merge remote-tracking branch 'origin/integration' into pwm
Bugfix in pio_conf_pin_to_peripheral() in pio.c
Modified definition-names in pio.h
Remoed a few warnings by editing bitwise_operations.c
Removed some warnings.
Wrote pwm_set_channel_period() in pwm.c
Wrote a manual test in main.c
Created tests for bitwise_operations.c
Created prototypes for the tests in test_bitwise_operations.c