Merge RPi and Arduino code

Merged code to simplify everything
- #31 Timing of stopListening() adjusted slightly to further prevent
blank ack-payloads if powering down while using ack-payloads or
switching between modes
Fix for last commit (code merge)

Prevent inclusion of BCM2835 driver for non-linux devices
Replace old examples with the current ones for RPi

Accidentally copied old RPi examples on last commit (code merge)
Moved RPi SPI driver to RPi folder from root

- Moved bcm2835.h and .c to RPi folder
- Changed includes and makefile to accommodate
Incr delay in stopListening(); Fix transfer example

- Testing with Arduino & RPi indicates delay needs to be increased
slightly before flushing tx_fifo
- Fix addresses in RPi transfer example, and add stopListening()
Fix include for RF24_config.h
Fix header file install for RPi in Makefile
Slight fix for makefile and RF24.h define
Minor change to readme
Another correction RPi code merge (install info)

Error from merging of code
Python wrapper for RPi added
Reliability improvements for RPi

- In testing with python wrapper, found setting CE(HIGH) sooner in
startListening() prevents issues
- Changed delay between available() checking on RPi to prevent what
seems like saturation of the RF24 module with SPI requests
- Reduces errors when switching between RX/TX modes
Remove unnecessary delay

Further testing indicates this is not needed
Revert last commit, if defined... delay

Delay is necessary for faster devices in some cases
- reduced delay by 30us for testing further
Merge pull request #35 from mz-fuzzy/master

Python wrapper for RPi added

This wrapper and the pingpair_dyn example seems to have brought up a bit of a timing issue that should be fixed in the latest commit https://github.com/TMRh20/RF24/commit/d41d47ab20cb794b8250560154076b1b2b06feae  
Also, (minor issue) it seems to be missing the define for ```BCM2835_SPI_CS0``` and ```BCM2835_SPI_CS1``` 
That can be fixed, and it seems to work nicely otherwise, so merging.
Revert change to delay from last commit

Further testing after including python wrapper indicates the original
delay seems to be about this best its going to get as far as a
compromise between delaying a bit/throughput and reliability of payloads
when rapidly switching between modes.
Non-conflicting names

Using this library in a file along with iostream caused a compilation
error. The “#define min” line in RF24_config.h overrode a function by
the same name used in a file included by iostream. Renamed to avoid
this issue.
Intel Gallileo support added
optimization for Galileo Delay
Galileo Optimizations and FIFO Fix