[ARROW-986] [Format] Update IPC.md to account for dictionary batches

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.3.0
• Fix Version/s: 0.4.1
• Component/s: Format
• External issue URL: https://github.com/apache/arrow/issues/16584
• Assignee: Wes McKinney
• Reporter: Wes McKinney
• Created: 09/May/17 13:53
• Updated: 11/Jan/23 07:12
• Resolved: 05/Jun/17 10:20

Description

The document incorrectly states that dictionary encoding has not been implemented