This removes the memory leak and adds a move method to PeaksWorkspace

When IPropertyManager::getValue fails to assign the property to the
specified type, a runtime_error is raised. Changed the error messages in
all (specific) cases to specify exactly what type it was expecting,
i.e. (const) shared_ptr<X> not just X or const X.

Signed-off-by: Karl Palmen <karl.palmen@stfc.ac.uk>

Added non-virtual clone() interface with a virtual private doClone()
method to Workspace and derived classes. Workspaces that had a clone()
method before were adapted to have a common interface everywhere. In
cases where there was no clone() method previously we simply throw an
error for now, until this new functionality is implemented.

Some tests/mocks had to be adapted since there there is a pure virtual
doClone() in all abstract classes.

Do to smart pointer incompatibilities (mainly due to old boost versions)
we had do extract the raw pointer from the unique_ptr returned by clone
and put it into a boost::shared_ptr manually, in some cases. See also
issue 12949.

It is still backwards compatible with the old log-entry format.
Refs #11359

Refs #11359

Unit tested to ensure we are creating a self-consistent peak.
Expose to python and unit test there too.