Defined needed registers for the PWM in pwm.c
Added new API functions to the API-design. Possible duplications must be
removed later.
Defined register masks and defined parameters to be used in pwm.c
Added values to definitions of masks and parameters in pwm.c
Refactored function names in global_entities.h and .c
Code cleanup and refactoring to maintain consistency throughout the
pwm.c.
Added a large doxygen comment to global_entity.c.
Depricated set_section_in_register2() and announced this in doxygen
documentation.
Changed version to v0.3.