GNU Makefile Refactoring

[AmeyaVSingh]

Refactored the GNU Makefile to be generic:

• Generic BOOST Library include and library path resolution.
• Support for static and dynamic linking with boost libraries.(Using STATIC_LINK=1 or STATIC_LINK=0 respectively in make command)
• Extending compiler flag support using:
  • CXXFLAGS and CFLAGS for C++ and C sources.
• Other minor fixes for missing command line parameters.
• Support for out-of-source builds.
• Cleaner support for compiler generated dependency file generation.

[jrahmeh]

Many thanks for the nice work on GNUmakefile. I merged it.