Fix escapeString to handle parameters that contain spaces.

[MadManMarkAu]

escapeString will escape a single parameter containing spaces into a string CasparCG will interpret as being multiple parameters. If a parameter contains a space, it should be surrounded with quote marks.

[tjenkinson]

Thanks for this. I agree that this makes sense but I think either it should be another method which will escape and quote (if needed), or a second parameter which would default to false, but if true add the quotes (if necessary). That way it won't break code for people that have already wrapped this function call in quotes, which could result in duplicate quotes, so it's backwards compatible. If you add this change I'll merge it in :)