Cleaned and organized enet_udp
Converted adis project to common boardfile

This moves all of the ADIS specific pin settings to
the ADIS16405 driver. In the interests of simplicity
I just cut and pasted the functionality but in the future
it should be made more pin abstract.
Converted datap_imu_a to common board file
Converted datap_rc to common board file

Also added a .gitignore
Converted extintr to common board file
Updated gps to the common board file
Changed gpt_exp to the common boardfile
Changed mailbox_test to the common boardfile
Converted mpu to the common boardfile
Changed pressure_sensor to the common boardfile

Since it depends on usb_cdc it still doesn't build.
Changed PWM to the common boardfile
Added comments and some ethernet cleanup