FLUME-315: Skeletal Developer Guide

Review Request #1165 - Created Nov. 4, 2010 and submitted

Bruce Mitchener
FLUME-309, FLUME-315
esammer, jon, phunt
This provides a skeletal Developer Guide with some notes on writing logging code.

It is slightly different from the UserGuide and cookbook in that i put it in a directory of its own ... that's because images for all 3 documents would be in the same directory if I followed how UserGuide and cookbook were done and I didn't feel comfortable with that.