Merge pull request #555 from mcnewton/v3.0.x

sqlite doesn't have NOW() or INTERVAL
Use "next" instead of "node"
Replace NOW() with date('now') in sqlite accounting queries. Oops.
Suppress more xlat debugging
Don't indent debugging messages so much
Remove extraneous ?.  It's ugly
Fixup formatting of SQL queries
If the module was optional (-sql) it's real name is "sql"

So that the debugging output is clearer
Fix a few more minor issues
oreect Message-Authenticator calculation for CoA packets.

Patch from Jouni Malinen.
Note changes
Document unlang changes, and other cleanups
Document all new modules
Add ToC
Re-organization for clarity
last re-arrangement
Another typo
Minor tweaks
Add ToC
Add "retry_delay".

And re-set "last_failed" if we managed to open a connection