Add 6.0.0 CHANGELOG entry

For the upcoming release.

CHANGELOG.md

@@ -1,3 +1,83 @@
+### citus v6.0.0 (November 4, 2016) ###
+
+* Adds compatibility with PostgreSQL 9.6, now the recommended version
+
+* Removes the `pg_worker_list.conf` file in favor of a `pg_dist_node` table
+
+* Adds `master_add_node` and `master_add_node` UDFs to manage membership
+
+* Removes the `\stage` command and corresponding csql binary in favor of `COPY`
+
+* Removes `copy_to_distributed_table` in favor of first-class `COPY` support
+
+* Adds support for multiple DDL statements within a transaction
+
+* Adds support for certain foreign key constraints
+
+* Adds support for parallel `INSERT INTO ... SELECT` against colocated tables
+
+* Adds support for the `TRUNCATE` command
+
+* Adds support for `HAVING` clauses in `SELECT` queries
+
+* Adds support for `EXCLUDE` constraints which include the partition column
+
+* Adds support for system columns in queries (`tableoid`, `ctid`, etc.)
+
+* Adds support for relation name extension within `INDEX` definitions
+
+* Adds support for no-op `UPDATE`s of the partition column
+
+* Adds several general-purpose utility UDFs to aid in Citus maintenance
+
+* Adds `master_expire_table_cache` UDF to forcibly expire cached shards
+
+* Parallelizes the processing of DDL commands which affect distributed tables
+
+* Adds support for repartition jobs using composite or custom types
+
+* Enhances object name extension to handle long names and large shard counts
+
+* Parallelizes the `master_modify_multiple_shards` UDF
+
+* Changes distributed table creation to error if the target table is not empty
+
+* Changes the `pg_dist_shard.logicalrelid` column from an `oid` to `regclass`
+
+* Adds a `placementid` column to `pg_dist_shard_placement`, replacing Oid use
+
+* Removes the `pg_dist_shard.shardalias` distribution metadata column
+
+* Adds `pg_dist_partition.repmodel` to track tables using streaming replication
+
+* Adds internal infrastructure to take snapshots of distribution metadata
+
+* Addresses the need to invalidate prepared statements on metadata changes
+
+* Adds a `mark_tables_colocated` UDF for denoting pre-6.0 manual colocation
+
+* Fixes a bug affecting prepared statement execution within PL/pgSQL
+
+* Fixes a bug affecting `COPY` commands using composite types
+
+* Fixes a bug that could cause crashes during `EXPLAIN EXECUTE`
+
+* Separates worker and master job temporary folders
+
+* Eliminates race condition between distributed modification and repair
+
+* Relaxes the requirement that shard repairs also repair colocated shards
+
+* Implements internal functions to track which tables' shards are colocated
+
+* Adds `pg_dist_partition.colocationid` to track colocation group membership
+
+* Extends shard copy and move operations to respect colocation settings
+
+* Adds `pg_dist_local_group` to prepare for future MX-related changes
+
+* Adds `create_distributed_table` to easily create shards and infer colocation
+
 ### citus v5.2.2 (November 4, 2016) ###
 
 * Adds support for `IF NOT EXISTS` clause of `CREATE INDEX` command