Site: change overview video, add it to readme
DBMaker: improve extendability
Git: ignore symlinks
Store: add some basic logging
DataOutput2: remove unnecessary calls
DataOutput: add unit test
Volume: change 'chunk size' from 1GB to 16MB and disable incremental allocation. The 'full chunk allocation' option was removed and is now on by default.

This change completely changes  storage format, there is no backward compatibility with previous versions.

This solves race conditions while byte[] was being copied inside in-memory store. It solves issues #302 and #303
Maven:  do not run tests in parallel, it causes out of memory errors
StoreWAL: do not delete log file after every commit, keep it around so commits are faster
Engine: add close listener, to prevent NPE on shutdown in HTreeMap Cache.
Queues: fix offer method not returning false. See #300
DBMaker: method `newDirectMemoryDB()` replaced with `newMemoryDirectDB()`
Queues: add simple test case from mailing list.
[maven-release-plugin] prepare release mapdb-0.9.11
[maven-release-plugin] prepare for next development iteration
Site: add news about MapDB 0.9.11 release
my change
Merge remote-tracking branch 'upstream/master'

Conflicts:
	pom.xml