Go over training course wiki pages

[Peter Parker]

Too many changes are needed to list them all here. General areas that need a polish:

• Some of the example code has incorrect or old-API-style syntax.
• Lot's of typos.
• Some of the exercises could be worded a little better to give readers a clearer idea as to what is required.
• The page order of the printouts for "Extending Mantid With Python" was really messed up in places.
• Other bits and bobs.

[Peter Parker]

No code changes for this ticket.

I made some changes to the course pages where we'd come across mistakes previously.

I'd still say they were a WIP, though.

[Andrei Savici]

Updated some python links to point to the generic version 2 instead of 2.5. Updated exercise 4 in Extending Mantid with Python

[Stuart Campbell]

This ticket has been transferred to github issue ​9302