Remove 'who' argument from xq functions
mapper: Replace malloc with calloc
mapper: Handle X_UPDATE op
python: Add X_UPDATE op support
python: Fix typo in variable name
mapper: Zero out buffers before writing objects
peer: Fix uninitialized old_pid value
filed: Create all files with RW group permissions
peers: Adjust umask for all peers

Adjust umask for all peers to S_IWOTH, to ensure that every file can have RW
permissions for the group.
archipelago: Adjust permissions of directories

Make all Archipelago directories, files and fifos accessible by the group
Archipelago is configured to run as. This way all Archipelago components can
communicate and signal each other independently from their effective user id.
archipelago: Move cephxid to Radosd class
mapper: Fix mapper log message
archipelago: Fix None value for v0_size
conf: Change the default user/group to archipelago
Minor python fixes
python: Return a more descriptive message on xseg_join failure

If xseg_join fail, raise an Error with a more descriptive message based on
errno.
filed: Create dirs with RW permissions for group
peer: Always use posixfd peer type
filed: Use '\0' for NULL termination

Use '\0' for NULL terminating strings instead of 0.
Also adjust max string size for the archipelago dir where the files are located.
filed: Add separate directory for locks

Add a separate directory for locks. If this directory is provided, filed uses
this directory to place the lockfiles. Otherwise, it falls back on the previous
behavior.