The new non-loading tests should be sufficient.

Mostly the addition of const in several places.

Conflicts:
	Code/Mantid/Framework/ICat/src/ICat3/ICat3Helper.cpp
Refs #7639.

- In order to search for datetimes the format needs to match the server's. This is in the form of: `Y/M/D h/m/s`.

change mtd[ws] == None to not mtd.doesExist(ws)

re #7863

- Note: This currently works on windows as file paths are not modified for other operating systems, and the mount point of the archive is not taken into account.

Nothing to do with this ticket, but this gave a ton of warnings when
built with clang and if you look at it it was clearly nonsense.
(N.B. nd is properly initialised later in the constructor.)

If there is no next entry, NXgetnextentry will not have set the nxname
& nxclass variables that were passed to it. Therefore, a valgrind
complaint is avoided by checking for success & only coping the variables
on success.

A boost::shared_array should be initialised with NULL or a pointer to an
array, so what was there were errors. In fact, in these cases there's no
need for any initialisation, only declaration.