Renamed CLI_AMI_ERROR to CLI_AMI_RETURN_ERROR, to clarify that this command returns immediatly. Use printf format in CLI_AMI_RETURN_ERROR. Fixed SCCPMessageDevice (missing one comma in CLI_AMI_PARAMAS). Rectified use of CLI_AMI_ERROR in sccp_conference.

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4801 43c1dc8c-776e-4df2-8ef1-6e829299be21
Clarify use of cli-function : 'sccp set' (still a little murky)

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4802 43c1dc8c-776e-4df2-8ef1-6e829299be21
Update error message from SCCPMesaageDevice(s)

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4803 43c1dc8c-776e-4df2-8ef1-6e829299be21