This branch is for development of Checkpointing [0,1].

Specifically, this branch is for Checkpointing backed by a series of patches
stored within the WC, referred to as design "option 1" in [1].


== What Kind of Branch? ==

Branch type: dev branch off trunk; updated by full merges from trunk;
not yet intended to be merged to trunk.

The following branching hierarching shows the intended propogation of changes,
although the actual copy history of the branches is not as shown here.

    trunk          ------------------------   catch-up
                           \ \                 merges
                            \ \                |   |
    branches/checkpoint      \ +-----------    V   |
                              \                    |
    branches/checkpoint3       +-----------        V

Initially this is prototyping, to explore the general shape of the design and
user interface. As such, it does not take care over details of APIs and error
handling and so on.


== What Functionality is On the Branch? ==

(Differences, relative to trunk.)

* supports read/write of shelf revprops (incl. log message) by this syntax:
    svn prop* --revprop -r SHELF_NAME.VERSION ...


== References ==

   [0] dev@ thread "[RFC] Shelving and Checkpointing", J Foad, 2017-07-10.
   [1] Shelving-Checkpointing Dev doc. (J Foad)
https://docs.google.com/document/d/1PVgw0BdPF7v67oxIK7B_Yjmr3p28ojabP5N1PfZTsHk/