[HBASE-27513] Modify README.txt to mention how to contribue

• Type: Task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.6.0, 3.0.0-alpha-4, 2.4.16, 2.5.3
• Component/s: community
• Hadoop Flags: Reviewed

Release Note

Remove README.txt and replace it with README.md.
Add a 'How to Contribute' section to tell contributors how to acquire a jira account.

• Assignee: Duo Zhang
• Reporter: Duo Zhang
• Created: 01/Dec/22 10:43
• Updated: 06/Jan/23 00:51
• Resolved: 10/Dec/22 13:20

Description

Especially how to acquire a jira account.

Will file other issues for changing other resources such as website and ref guide.

Issue Links

• links to: GitHub Pull Request #4913