Add and maintain History for workspaces

[Nick Draper]

The history needs to contain several sections.

1. An environment sections containing
   1. The version of Mantid
   2. The OS name and version
   3. The user name
2. The algorithm History of a workspace (i.e. for every algorithm that has been run on this workspace of it's parents).
   1. The name and version of the algorithm
   2. The date and time applied
   3. The values of every alogirthm property
   4. How long the algorithm took to run

The majority of the History data filling can take place in the Workspace Factory. If we change the main factory method to take (string workspaceType, Workspace parentWorkspace, algorithm currentAlgorithm) then the workspace would have all of the info required to.

1. Copy all of the History from the parentWorkspace to the new one
2. Create a new algorithm History record from the current Algorithm

We may need to think later about how we handle branched histories. eg. WS1 = LoadRaw("file1") WS2 = LoadRaw("Vanadium2") WS3 = WS1/WS2 At this point WS3 would need to contain the history of both WS1 and WS2

[Nick Draper]

duplicate of #58

[Alex Buts]

refs #37 Merge branch 'master'

Conflicts:

Code/Mantid/Framework/Kernel/inc/MantidKernel/ValidatorSignalChange.h

Changeset: 5c9639416a56b09180a6a4d4407132d69b3f0aa2

[Stuart Campbell]

This ticket has been transferred to github issue ​885