doc - Simplify the upgrade directories

It overcomplicates things to have one folder for every version change
when many times no special action is needed.
Most uprades that contain no schema changes are simply 'sync and restart'.

Thus, only create folders when work is actually needed.
All other upgrades can be rolled into a single "XtoCurrent" folder,
with instructions to sync and restart.

Basically this change is:
- Rename folders to match times when the schema changes (2.0 -> 3.2 -> Current)
- Only have one folder for each time the schema changes
- Everething else can fit into a '3.2toCurrent' folder
notary_http - Remove unneeded parameters from calculate_service_xml()
CHANGELOG - Add notes on work from this branch
Merge pull request #49 from daveschaefer/fix_upgrade_docs

Fix upgrade docs