Add exception handling for external consumer scripts.
Add exception handling for xxxLinuxKernelCmdline and xxxStringInFile.

Changed :

FindStringInFile
ReplaceStringInFile
FindInLinuxKernelCmdline
AppendToLinuxKernelCmdline
RemoveFromLinuxKernelCmdline
ApplyVNUMAWorkaround
RevertVNUMAWorkaround
SharedConfig.Parse
HostingEnvironmentConfig.Process
Agent.Run
Modified GetMyDistro() to accept optional specification of distro name for test support.
Added self.service_cmd to AbstractDistro

Changed:
GetMyDistro()
AbstractDistro.startAgentService()
AbstractDistro.stopAgentService()
AbstractDistro.restartSshService()
SuSEDistro.service_cmd
FreeBSDDistro.restartSshService()
Ensure correct unicode encoding is used for ovf.xml.
Better detection and removal of BOM.

Changed:
Agent.Provision