document release process

[drwells]

to keep things tidy lets do the following:

• tag the last commit before we branch vX.0.0
• create a new branch fiddle-X
• increment FDL_VERSION_MINOR on fiddle-X and tag that commit as vX.1.0
• increment FDL_VERSION_MAJOR on master

This way it is clear that (normal) development stopped at the vX.0.0 tag and makes the history cleaner (all commits added between version vX.1.0 and vY.1.0 are between vX.0.0 and vY.0.0)