lsyncd additions

this goes with the gcl i had made for the build script (and have a new gcl to support sending signals)
- support 'exchange' fsevents, which are used by editors to make atomic saves (someone had requested this, but the maintainer wanted to punt until he rewrote the fsevent support)
- write to the log file whenever something changes, so the build knows if lsyncd is clean or not
- be able to instantly fire off a sync when trying to build when lsyncd has changes and is waiting in hopes of collecting more in the 'delay' interval

that last point needs the desktop user to add something like this to their sudoers file so a signal can be sent without a password
ALL   ALL = (ALL) NOPASSWD: /usr/bin/killall -USR1 lsyncd, /Volumes/hrt/lsyncd/lsyncd