Proposal: X.Y versioning scheme

[effigies]

Was discussed in the sprint but never written up.

BIDS Stats Models will have a two-part versioning scheme, X.Y. A version 1.0 will be said to have "major version" 1 and "minor version" 0. This number MAY be used in the BIDSModelVersion.

This repository will have a three-part versioning scheme, X.Y.Z where X.Y corresponds to the BSM version number. Z will be known as the "micro version" and will be used to tag releases of the documentation and schema that fix inconsistencies and incompleteness in the X.Y version without modifying the meaning of the specification. This full number MAY also be used in the BIDSModelVersion, but implementations are expected to do their best to parse a file according only to the X.Y.

We should be very cautious about incrementing the micro version when it modifies the schema in any way; generally if non-pathological models validate in X.Y.Z, they should continue to validate in X.Y.(Z+1).