Merged documentation changes from trunk:
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r55668 | chris_kohlhoff | 2009-08-20 08:29:34 +1000 (Thu, 20 Aug 2009) | 2 lines
Add revision history to docs.
r55670 | chris_kohlhoff | 2009-08-20 08:44:02 +1000 (Thu, 20 Aug 2009) | 2 lines
Clarify that deadline_timer uses a UTC-based clock by default.