Allow setting of dynamic vars for MQTT's username and password:

* This allows pulling out the values of the username and password if set as dynamic vars.
* Essential to load an external file with usernames and password.
Merge pull request #83 from rodo/master

Should fix float in thinktime substitution
Merge pull request #81 from baz44/mqtt_dynenvs

Allow setting of dynamic vars for MQTT's username and password:
doc protocol_local + sort protocol logs
Add new function to initiate an ets:table from external modules
wait for all ts_stats_mon procs before stopping (TSUN-298)
Merge pull request #84 from rodo/newets

Add new function to initiate an ets:table from external modules
tag parallel map messages to avoid receiving other messages
test if cpu mon value is available (TSUN-295)
Merge branch 'master' of github.com:processone/tsung into github
Will fix TSUN-286
Add 2 more tests to increase coverage