[HADOOP-12019] update BUILDING.txt to include python for 'mvn site' in windows

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.8.0, 3.0.0-alpha1
• Hadoop Flags: Reviewed
• Assignee: Vinayakumar B
• Reporter: Vinayakumar B
• Created: 22/May/15 09:57
• Updated: 30/Aug/16 01:27
• Resolved: 04/Jun/15 05:18

Description

HADOOP-11553 introduced shelldocs.py to generate documents for shell APIs. This needs python to execute.

In Linux environments python available by default, but in windows needs to be installed separately.