Update BSON_README.md

Completed unfinished statement about which settings turn off reading and writing of splits information
Optimized BSONComparator's compare
Added Lazy BSON as a format type
Merge pull request #70 from solarmicrobe/patch-1

Update BSON_README.md
Verify that there is a valid output URI set before trying to write any records HADOOP-81
Merge pull request #72 from sweetieSong/issue/add-lazybson-input

Added Lazy BSON as a input type
move environment-specific settings to the top of script, set in bash vars
Merge branch 'master' of https://github.com/mongodb/mongo-hadoop
round-robin target shards by re-ordering splits/chunks for sharded collections.
support for multiple collections
move splitter classes into their own package, pull all settings from Configuration instances.
remove old splitter classes from util/ since they will now live under splitter.*
use localhost for mongoimport to avoid ns not found in auth tests.
put teardown back the way it was
Use github-flavored markdown so we get syntax highlighting.
add more syntax highlighting to readme
fail more gracefully on timeout, and extend timeout length when starting up mongod.
fix tab/space on indent.
formatting cleanup.
Convenience method for setting up multiple collections from within java code.