BUG-1200 changed help for agentpath && added comment describing functions.sh

- added full path when sourcing functions.sh - now 'run.sh -help' will
  work other then current directory

Change-Id: I5988b86ed0eeab8f6251a694a5c40d48c505966d
Signed-off-by: Jakub Toth <jatoth@cisco.com>
Signed-off-by: Michal Rehak <mirehak@cisco.com>
Merge "BUG-1200 changed help for agentpath && added comment describing functions.sh"