Added basic chroot support, added option to configure.ac.
Added basic chroot support
Merge branch 'bfgminer' of github.com:corrideat/bfgminer into bfgminer
Merge branch 'bfgminer' of github.com:corrideat/bfgminer into bfgminer
Updated miner.c
Merge branch 'bfgminer' of github.com:corrideat/bfgminer into bfgminer

Conflicts:
	miner.c
Update miner.c
Improvements on code
Replace u-hashrate with nonce-based hashrate adjusted for rejects/stales
Merge commit '36aac1c' into bfgminer
Bugfix: Use correct configure define for pwd.h
Remove --disable-chroot build option: always compile --chroot-dir if supported
Bugfix: Use correct configure define for chroot
README: Document new --chroot-dir and --setuid options
Merge branch 'chroot' into bfgminer