[NUI] Change the Regex member variables of InputFitler to string

[NUI] Change the Regex member variables of InputFitler to string

The properties of the NUI InputFilter require a regular expression.
But internally DALi uses std::regex.
When passing a regex from NUI to DALi, it is passed as a string.
So the platform can not guarantee all the features of C# Regex (RegexOptions etc).

Signed-off-by: Bowon Ryu <bowon.ryu@samsung.com>