Add task termination status to result
Adds signal, resources exhaustion and task timeout as results
Changes status to exit_status at worker
Report task_status in result
Changes list priority from int to double.

This allows an easy implementation of something like A* in work queue,
while preserving the old int behaviour.
Merge pull request #535 from btovar/separate_task_result_exit_code

Separate task result and exit code
Expire tasks by end time, at the master
Add python binding
Mark expired completed tasks at worker
Expire running tasks at worker
Add missing header.
Merge pull request #538 from btovar/expire_tasks_by_end_time

Expire tasks by end time
Merge pull request #559 from btovar/priority_double

Changes list priority from int to double.
If connection fails during auth, retry.

chirp_client_connect would treat any failure during authentication as EACCES
which would prevent chirp_reli from retrying. This caused the chirp tool to
fail for Anna/Charles in their experiments.

This commit also adds failure checking for all link calls.
If connection fails during auth, retry.

* chirp-auth-disconnect:
  If connection fails during auth, retry.
sort headers
simply use buffer library
Use 64 bit buffer lengths.

This is pulled out of the Confuga branch where we want to able to hash large
files. This commit also changes the <hash>_file routines to use mmap if
possible.
add work_queue_priority_test to .gitignore
Add helper macros for creating a stack buffer.