Better handling of breakpoints across threads.

src/e-server:
	* src/GdbServer.cpp (GdbServer::rspRemoveMatchpoint): Ensure
	breakpoints are set in all threads.
	(GdbServer::rspInsertMatchpoint): Likewise.
	* src/TargetControl.h: Add isLocalAddr () as public pure virtual
	method.
	* src/TargetControlHardware.cpp
	(TargetControlHardware::isLocalAddr): Created.
	(TargetControlHardware::convertAddress): Use isLocalAddr.
	* src/TargetControlHardware.h: Add isLocalAddr () as public
	method.