libbladeRF: Added doxygen generation to build if Doxygen is installed.
libbladeRF: Doxygen generation for 'make doc', not 'make all'
libbladeRF: Fixed Doxygen paths
libbladeRF: Fixed return value in libusb backend's change_setting()

This routine was returning a libusb error code, not a libbladeRF code.
libbladeRF: Reverting f34fbf6577b809c8432ca30b93d000d929ac4eb4
bladeRF-cli: Reverted ee364bba3e2c and fixed return value issue(s)

The underlying problem for Issue #43 was a return of -1 for any
failures, rather than an apppropriate CMD_RET_* code. Since -1 ==
CMD_RET_QUIT, this error would cause the application to quit (hence the
issue being labeled a "crash")

The reworked parsing has been rolled back since the parsing was not the
source of the issue. Changes from ee364bba3e2c will be cherry-picked
back in as needed.
bladeRF-cli: Fixed dangling FILE*

The following scenario was resulting in the assertion at line 235.
tx_csv_to_c16's interface specifies that it modiefies the file
descriptor -- in the failure case this means that it should close it
down.

```
bladeRF> tx config file=/dev/urandom format=csv

tx: Invalid I value encountered in CSV file

bladeRF> tx config format=bin
bladeRF> tx start
```
bladeRF-cli: Made csv->binary conversion more portable.

The use of mkstemp and the /tmp/ path would pose problems on the
windows side of things -- removed this.
bladeRF-cli: Removed binle/binbe options. Binary data is host endianness

These changes are based upon those provided by engidea for Issue #64,
with some additional little naming changes.

To avoid having to deal with compiler-specific endianness macros,
the fixup routines contain the converion macros even for the
little-endian host case, assuming these will be optimized out, given
that they are generally empty macros.
merging back master
merging back master