Cqlengine

[232] update docs w/ links to external tutorials
[229] get travis to test different cassandra versions
[211] inet datatype support
[209] Python 3 support

removed references to create_missing_keyspace

Create keyspace no longer defaults to SimpleStrategy with 3 replicas. It must be manually specified.
sync_table() no longer has an option to create keyspaces automatically.
cqlengine_test is now the default keyspace used for tests and is explicitly created
all references hardcoded to the "test" keyspace have been removed and use the default instead
instead of testing with bin/nose, use setup_package
improved validation error messages to include column name
fixed updating empty sets
improvements to puppet download script
per query timeouts now supported, see https://cqlengine.readthedocs.org/en/latest/topics/queryset.html?highlight=timeoutper-query-timeouts

Fixed tests with Cassandra version 1.2 and 2.1
Fixed broken static columns
support for IF NOT EXISTS via Model.if_not_exists().create()

[264] fixed support for bytearrays in blob columns

[260] support for static columns
[259] docs update - examples for the queryset method references
[258] improve docs around blind updates
[256] write docs about developing cqlengine itself
[254] use CASSANDRA_VERSION in tests
[252] memtable_flush_period_in_ms not in C 1.2 - guard against test failure
[251] test fails occasionally despite lists looking the same
[246] document Batches default behaviour
[239] add sphinx contrib module to docs