enabled its test and fixed (I believe unnoticed earlier) errors with file-backed operations.

It may be not very efficient file mode as one needs to identify the if the buffer for SaveMD make file based is defined correctly.

and small changes related to its enhancement.

for everything that is outside of ISaveable test

Separated it into ISaveable.cpp and Saveable and changed memory buffer

Fixing Crystal, Geometry, Kernel and WorkflowAlgorithms.

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

All file based workspaces have to use disk buffer now. If the disk buffer size is set to 0, the data are saved to HDD (or discarded if not modified) as soon as they are free.

small changes to algorithms too to incorporate new logic of working

ISavable now knows about its position in file and works together with the DiskBuffer to identify the location of the data in the file.

into Kernel

Fixes #3561: Copy constructors for MDBox, MDGridBox. Refs #3558: CloneWorkspace workspace for file-backed MDEventWorskpace.

Refs #3445: Start of a DiskMRU class. But mostly this was to remove the dependency on TestHelpers of API which makes building APITest slow.