Build notes

//-------------------------------------------------
// NOTICE - Transition to SCONS
//-------------------------------------------------

The IoTivity build system is transitioning to SCONS. Although the
makefiles are still available (until v1.0) and some developers are
still using them, they are currently no longer supported. To learn more
about building using SCONS see Readme.scons.txt in the repository root
directory. The build steps used in continuous integration can be found
in auto_build.sh which is also in the the repository root directory.

//-------------------------------------------------
// Linux
//-------------------------------------------------
To enable logging, ensure that
	-D TB_LOG
is set in the compiler flags

//-------------------------------------------------
// Android
//-------------------------------------------------
To enable logging for Android, TB_LOG should be defined in the ./jni/Android.mk file as

LOCAL_CFLAGS := -DTB_LOG

//-------------------------------------------------
// Arduino
//-------------------------------------------------
To enable the logger for Arduino, TB_LOG should be defined in
Properties|C/C++ Build|Settings|Tool Settings|AVR Compiler|Symbols
and
Properties|C/C++ Build|Settings|Tool Settings|AVR C++ Compiler|Symbols

Note: when building for Arduino, force the compiler to use avr-g++ to build logger.c.  Or rename logger.c to logger.cpp.

Note: when building for Arduino, several warnings are generated when trying to place strings in
PROGMEM
"warning: only initialized variables can be placed into program memory area"
This appears to be a known gcc bug - https://gcc.gnu.org/bugzilla/show_bug.cgi?id=34734