replace type juce::ScopedPointer with std::unique_ptr (@ 8cc06de)

[FulopNandor]

In the previous commit titled Eliminate the JUCE assertions in ''AboutBox'' (@ cd33b95), the variables dexed and surge were declared as juce::ScopedPointer in the AboutBox class, in the GlobalEditor.cpp file. Because this type is obsolete (see some discussions about it at JUCE Forum), it was replaced by std:unique_ptr - thanks to @baconpaul, who brought this to my attention.
Furthermore, the initialization of the variables dexed and surge has been moved back to the initializer list of the constructor of the AboutBox.