wip #47: register accessor for write after open in DeviceModule if write cannot be performed in initialisation phase

Issue81

		add bool thereHaveBeenExceptions
		write test for taht
			testExceptionsDummyDevice.cc

wip #47: add test for direct connections from ConfigReader to a device. The test is currently failing.

		writeAfterOpen writes constants to devices
		remove writeAfterOpen in recovery loop
			that should be in writeRecoveryOpen
		extend testProcessVariableRecovery for constants

  - Handle illegal writes to read-only accessors in doPreWrite().
    Otherwise, attempting to write to the recovery accessor would result
    in a nullpointer access.
  - Related test case.

	Ticket #79
	- documentation for addRecoveryAccessor() and getRecoverySharedMutex()

  - Cleaned up comments
  - Place using-declaration of buffer_2D to class definition so the base
    class name can be omitted in the implementation

forgot to commit latest change: testProcessVariableRecovery now tries to get exception by reading (not writing), currently failing

- remove "void ExceptionHandlingDecorator::setDataValidity(DataValidity newValidity)"
- add "void ExceptionHandlingDecorator::setOwner(EntityOwner* owner)" and remove owner setting in constructor

  - add list with shared ptr of transferElements for recovery write
  - add shared mutex

  - Cleanup:

    - Reorder code in Application::createDeviceVariable
    - Separated ExceptionHandlingDecorator constructors for writable and
      non-writable registers
    - cleaned up doPreWrite