added doxygen-style documentation to encoder.h and gpio.h
switched tenses, began documentation on pwm, motor, servo, and i2c
finished the rest of preliminary documentation, left TODOs in i2c and uart
added doxygen-style documentation to encoder.h and gpio.h
switched tenses, began documentation on pwm, motor, servo, and i2c
finished the rest of preliminary documentation, left TODOs in i2c and uart
removed unnecessary line in motor.h
merging
Merge pull request #21 from ut-ras/doxygen-documentation

Doxygen documentation