docs: add buxton(7) and buxtonctl(1)
docs: add buxton-api(7)

Individual man pages for each library function, with minimal code
samples, will follow later.
docs: add buxton.conf(5)
docs: add buxtond(8)
docs: add buxton-protocol(7)
docs: add buxton-security(7)
Update todo
Update todo
lib: remove obsolete symbol from the sym file
db: Use group and key name for memory key
db: abort on memory allocation failures
core: Add abort if buxton_array_add fails
security: Abort on memory allocation failures
db: Don't put actions in asserts as they can be removed
shared: Abort on daemon side allocation failures
shared: Abort serialize

For the database serialization functions, abort on memory allocation failure and
exceptional conditions.
cli: Add missing data label argument
cli: Fallback to direct if client open fails
Error handling patch 1

This is the first of the smaller, less intrusive version of the error
handling patch.

This patch simply cleans up our use of BuxtonStatus, in favor
of moving to int32_t based (errno.h) return codes

Signed-off by Brad Peters <brad.t.peters@intel.com>
shared: Allow 0 element messages

For unset notifications, we send a data list of length 0 to indicate the
value had been unset. In this case we must support serialization and
deserialization of messages with 0 elements.