some work on SCons build environment:
- banner is printed each time SCons is invoked
- "board" switch to select the target board
- "toolchain" switch to select which toolchain to use. Currently only mspgcc supported.
- "bootload" switch to select the location of the board (e.g. "COM30") to load the binary on. Currently only TelosB supported.
- "jtag" switch to select the location of the board to JTAG the binary on. Untested.
- "fet_version" switch to select the version of firmware running on the MSP-FET430uif. Untested.
- all built elements (object files, libraries, binaries, ihex) located in common build/ directory at the openwsn-fw root.