Changed Makefile to use bash from homebrew on Mac OS X

Homebrew (http://mxcl.github.io/homebrew/) is an alternative to
MacPorts, it installs all binaries in /usr/local/bin
Added *.dSYM to gitignore

These are automatically generated on Mac OS X
added rejecting code to while loop.
Merge pull request #217 from neffs/master

small changes for Mac OS X
Merge pull request #218 from sauttefk/e6-upstream2

make tftp work when TFTP_CRC_SUPPORT is enabled and no format string is ...
bootloader - isolate network config from other configs in eeprom
use the correct BOOTP-tag for the time server
prevent saving the mac-address when there is a bootloader
store number of programmed bytes to eeprom
calculate application-crc using the size stored in eeprom
Merge branch 'e6-upstream2' of github.com:sauttefk/ethersex into e6-beteigeuze

Conflicts:
	.gitignore