add code to set bitOrder for SPI
Add condition checks to terminate at Invalid Clock & Mode set
Fix SPIClass::transfer function to send and receive data
used txData and rxData to collect and transmit data to/from the SPI buffer
Set correct values of preprocessor symbolic constants
Add copyright statement for second author
Add line to load BB-SPI0-01 cape for spi0
Add working device trees for SPI and Remove the non-working one
Removed files BB-SPI0-00A0.dts and BB-SPI0-00A0.dtbo from overlay/
Remove lines setting the spi pins for gpio so the SPI cape can be loaded without errors
Added files BB-BONE-BACONE1-00A0.dts and BB-BONE-BACONE1-00A0.dtbo for spi pins as gpio mode
Add example to test SPI over bacon cape's shift register connected to 7Segment
Resolve warnings related to reinitialisation and '|' operator
Merge branch 'master' of https://github.com/bugobliterator/Userspace-Arduino into bugobliterator-master

Merging bugobliterator's work on SPI.