'TM_string not handled in switch' compiler warning

[slightlynybbled]

telemetry_core.c

void try_update_hashtable(TM_msg * msg)

During compilation: "warning: enumeration value 'TM_string' not handled in switch"

May want to include a default case or explicitly handle this case to reduce compiler warnings. I realize that it is only one warning, but larger projects can end up with many such warnings which can cause documentation to have to be written to justify leaving the warning or cause someone to fork your repository without keeping it up.