Update unofficial ocs agent to version 1.9.1

[jackburton79]

Summary of changes from 1.6.4 to 1.9.1:

• Fixed crash when the server host name was unresolvable
• Added decoding of screen manufacturer (so that it repors e.g. "Hewlett Packard") instead of the PNP ID (e.g. "HWP")
• Improved memory inventory
• Improved CPU detection (using DMIDecode, lshw and /proc/cpuinfo)
• Improved graphics card detection
• Improved OS name detection
• Improved network interfaces detection
• Improved handling of invalid urls
• Improved logging
• Removed option --use-baseboard-serial-number (no longer needed)
• Removed option --new-agent-string (no longer needed)
• Updated tinyxml to version 9.0.0
• Huge code cleanup