Delete workspace from ADS before algorithm starts if it will be replaced anyway

[mantid-builder]

This issue was originally TRAC 804

Original Reporter: Russell Taylor

For example, if you give LoadRaw an OutputWorkspace name that already exists in the ADS, you can tell before you commence exec that the existing workspace will be overwritten. Transient memory usage would be reduced if you deleted that one before you created the new workspace.

This can possible be implemented as a general feature in the Algorithm base class, but could certainly be easily put into LoadRaw.

[mantid-builder]

@NickDraper (2009-09-23T14:50:18):
Moved as part of the end of Iteration 19

---

@NickDraper (2010-02-15T10:44:35):
Implement as a specific change to LoadRaw, Load???Nexus

---

@NickDraper (2010-12-16T09:49:23):
Bulk move of tickets to iteration 27, if your ticket is essential for Iteration 26 then move it back.

---

@NickDraper (2011-02-15T09:09:27):
Bulk move of tickets at the end of iteration 27

---

@NickDraper (2011-04-27T07:35:55):
Bulk move of tickets at the end of iteration 28

---

@NickDraper (2011-06-10T13:22:28):
Taken from Sofia Antony's list after she left

---

@NickDraper (2011-06-27T08:20:23):
"New" tickets moved at the code freeze of iteration 29

---

@NickDraper (2011-08-31T15:32:43):
Repeting from before:

'''Implement as a specific change to LoadRaw, Load???Nexus'''

---

@NickDraper (2011-09-19T09:30:47):
Bulk move of tickets to iteration 31 at the iteration 30 code freeze

---

@NickDraper (2012-01-09T09:43:22):
Moved to iteration 33 at iteration 32 code freeze

---

@NickDraper (2012-04-30T14:13:21):
Moved at end of release 2.1

---

@NickDraper (2012-08-10T12:43:57):
Moved at the end of release 2.2

---

@NickDraper (2012-10-28T11:39:11):
Moved to milestone 2.4

---

@NickDraper (2013-01-28T09:23:23):
Moved at the code freeze for release 2.4

---

@NickDraper (2013-04-29T09:50:00):
Moved to r2.6 at the end of r2.5

---

@NickDraper (2013-07-26T13:55:02):
Moved to backlog at the code freeze for R2.6

---

@NickDraper (2014-02-14T11:07:55):
bulk move to assigned at the into of the triage step

[NickDraper]

This is no longer required