Update to Impala v0.3 beta refresh release
Impala code refresh v0.3 -> v0.4 (pre-release version)

* Fix bug in string comparison with empty strings.
* Enable the shell to consume erros and continue for batch processing.
* Fix lpad string function.
* Fix Impala shell ignores TStatus return values
* Fix crash in TopN node with null tuples.
* import saslwrapper instead of sasl for Centos/Rhel
* Add user option to refresh catalogue after connection
* Impala build needs to work on Python 2.4 ("with" keyword not supported)
* Impala server raise exception if query_option is invalid
* Fix linker dependencies.
* print number of scanned partition and total scaned bytes
* INSERTS into unpartitioned tables should be checked for union compatibility
* Add profile counters to data stream sender/receiver.
* Change default for block-metadata enabled to use HDFS default.
* Add Twitter bootstrap to www/
* Improve debug webpage presentation
* Add arguments to webpage callbacks, and add simple fixed-size query log
* Add command line options to the shell which specified which database to use after connecting.
* Store and display results in batches for the shell to not overload memory.
* Allow webserver pages to optionally exclude themselves from navigation
* Bumping version to v0.4
* Fix planner to reject compressed text formats.
* Added missing volume id to webpage metrics.
* Added debug/release to version string.
* Added counter for number of scan ranges per file format/compression type.
* Add the ability to store cross session command history in the shell.
* Fix race condition in opcode registry.
* The shell should display verbose output by default. Add a flag to disable.
* Fix limit issue in exchange node.
* Fix codegen handling of \N (null) for non-string columns.