I installed the shelve extension for hg by adding 'shelve=' to [extensions]. I can verify this by running 'hg help extensions' which has the following in the output:
enabled extensions:
extdiff command to allow external programs to compare revisions
fetch pull, update and merge in one command
shelve Manage shelves of pickled objects.
I then type 'hg shelve' in a repo of mine, and I get:
hg: unknown command 'shelve'
Mercurial Distributed SCM
...
I would expect the shelve extension to run...
Mercurial verison is 2.0.2