Optimize ObjectImpl<>::GetDefault*().

Refs #2710
Implement String::FindFirstNotOf.

Refs #2710
Update gdbinit path.

Refs #2710
Implement additional operators for the Value and String classes.

Refs #2710
Implement performance data parser.

Refs #2710
Use PluginUtility::{Parse,Format}Perfdata for check results.

Refs #2710
Merge branch 'feature/perfdata-2710' into next

Fixes #2710