Fixed incorrect XMEGA DFLL reference frequency (thanks to Martin Aakerberg)
Fix AVRISP-MKII status values to match the published protocol (thanks to Gustavo Souza).
Fixed spurious 0xFE USART byte sent in the USBtoSerial project when the baud rate is changed (thanks to Carl Kjeldsen).
Ensure BulkVendor received data is cleared before reading from host.
Add COMPILER_PATH optional variable to the BUILD build system module.
Fix possible infinite loop in the control stream write template functions.
Fix missing report IDs in feature reports

As it is the case for input reports, the ID has to be sent for feature
reports when a device has multiple reports implemented.

Signed-off-by: Bert van Hall <bert.vanhall@avionic-design.de>
Merge pull request #28 from The-42/fix-feature-id

Fix missing report IDs for HID device class GetReport request responses (thanks to Bert van Hall).
Update documentation for HID report ID fix.
Add Serial_IsSendReady() and Serial_IsSendComplete() serial driver API functions.
Only deque from the USBtoSerial's USB->USART buffer when the USART is idle.
Update bootloader documentation to include execution instructions.
Minor documentation improvements.
Fix XMEGA USB prescaler calculation

The USB prescaler calculation for the CLK.USBCTRL register is changed to
give valid results and set the prescaler correctly.

Signed-off-by: Bert van Hall <bert.vanhall@avionic-design.de>
Merge pull request #32 from The-42/fix-xmega-usb-prescaler

Fix XMEGA USB prescaler calculation (thanks to Bert van Hall).
Minor code style fixes, documentation improvements.
Fixed USART reception overrun corrupting the internal buffers in the USBtoSerial project.
Fix Serial_XMEGA.h syntax and define error
Merge pull request #35 from hellprototypes/sandbox

Fix Serial_XMEGA.h typos.
Update Doxygen confiuration files to 1.8.8.