initial support for LZ4 compression
new docs on logging
another log fix
fix to string error
Merge branch 'master' into druid-0.7.x
rework the readme
Merge branch 'master' into druid-0.7.x

Conflicts:
	README.md
Merge branch 'master' into druid-0.7.x
Merge branch 'master' into druid-0.7.x
make LZ4 the default compression strategy

- LZ4 is now hardwired to be the default strategy
- Rework tests to test all available compression strategies
refactor FixedSizeCompressedObjectStrategy
Merge branch 'master' into druid-0.7.x
Merge pull request #632 from metamx/lz4-compression

Change default column compression from LZF to LZ4
update pom~
Merge branch 'druid-0.7.x' of github.com:metamx/druid into druid-0.7.x
Merge branch 'druid-0.7.x' into new-init