use const keyword at (some) appropriate places
introduce new function to emit warning and other non-error messages

also refactor the error message subsystem a bit
nit: update copyright dates
emit internal message when action is suspended and resumed
bugfix: action suspend timeout was not increased
add new impstats action counters:

  * suspended
  * suspended.duration
  * resumed
actions now report if they suspend and resume themselves
doc: create skeleton for global() config object
Merge branch 'v7-stable' into v7-devel
fix merge problem
document new global parameter
Merge branch 'v7-devel' into tmp

Conflicts:
	action.c