Applied performance optimization for queues.
fixed tests
added dispatcherThreads
changed the way of downloading user queries
merge
added progess indicator view
removed ajaxStart function
towards new dispatcher interface
Clarified variable names in worker and messageque
Merge branch 'devel' of github.com:triAGENS/ArangoDB into pregel

Conflicts:
	lib/BasicsC/errors.dat
	lib/BasicsC/voc-errors.h