#70 torc::physical find config by design name

[Neil Steiner]

Create a utility function in torc::physical to permit finding configs by design name. In most cases the user does not care about the instance and doesn't know the instance name, but is instead interested in a named element like a LUT or flop.

The function would have to iterate over all configs for each instance do find the specified name. A possible prototype would be:

bool Circuit::findConfigByName(const string& inName, InstanceSharedPtr& outInstancePtr, string& outSetting);