Allshare

This is a stab at fixing issue #247 which also revealed a bigger bug, namely that unescaped backslashes were being eaten by ```PropertiesConfiguration``` when parsing renderer confs (which broke the corresponding regexes).

Would appreciate volunteers to test with Samsung AllShare, plus would be great if anyone can help evaluate its impact on other possibly backslash-containing values (```OverrideVideoFilter```, ```CustomMencoderOptions``` etc).