ServerAnnounceObserver.update() updates last_update
Extend Observers Section

Added sections for MultiplexingObserver and ServerAnnounceObserver.
If numpy has a problem reshaping data, issue a warning instead of crashing

Addresses #1038
Ignore corrupt chunks from .get_chunks() in genpoi

See #1038
Have overviewer --version --verbose print some helpful information
multiprocessing-based POI generator no longer crashes on python 2.6

fixes Issue #1041
tileset: Typo fix
tileset: Render in expanding order from center
tileset: Unify _posttraversal_helper and _iterate_helper
Update test_posttraverse to match expanding order
test_all: import logging
test_settings: ValueError → MissingConfigException
test_settings/test_manual: Match renders order with file
test_tileset: Add missing world parameter
test_tileset: Add required name item to defoptions
test_tileset: Drop unused correct_tiles list
test_tileset: Depth is now 5 because of ‘maxrow + 32’ in tileset.py
.travis.yml: Run the test suite
.travis.yml: MC_VERSION=1.7.4
.travis.yml: Add IRC notifications