finally managed to cook up a test that is sensitive to the connection errors when using hierarchy modifiers

This closes #29.

Refactored.

Manual check to be used temporarily.

These additions cover the behavior described in #29.

  - Rename, this does not test the intial value propagation
  - Remove debug output

This reverts commit a80ebc2d.

This was the wrong approach, see ChimeraTK/DeviceAccess-DoocsBackend#45

It was agreed to never do this. What strings are for display only and should not be analysed, neither by tests nor by applications.

This helps understanding where an error is coming from, e.g. when multiple devices are used in the same logical name mapped device

This greatly helps debugging real setups, as the messages will usually end up in the server log.
Note: Ideally, a proper logging mechanism should be used instead, but this does not yet exist!

Reading was done only in deeper levels inside the VariableGroups.

See 1af92147. Input accessors are now properly part of the ReadAny group which improves the deterministic behaviour.

This provides a strict guarantee for the order of updates w.r.t. trigger, especially for tests.

  - Removed extra call to registerModule which caused multiple creation
    of the same module on a tree node
  - Made addChildNode private

Instead of holding the modules in a flat list as before, this represents
the ownership of nested modules correctly and prevents possible memory
access violation on destruction.

Automatically adding CMAKE_CXX_STANDARD to all projects is giving too much trouble because different CMAKE versions add different --std=gnu... flags which do not play well the the --std=c++... which we use.

This reverts commit ddb4d575.