Move glossary to main documentation index
Move glossary referenced docs under glossary.

Change index toctree to point to glossary index.
Update link in development docs to jsondumpstorage

Move required images under glossary directory.
Rename 'Development Discussions' to 'Contributing'
Fix reference in index to development document

Fixes bug 1040248
Merge pull request #2228 from bramwelt/fix-bug-1040248-development-documentation

Rename 'Development Discussions' to 'Contributing'