Write release entry and exit guidelines

[michaelchin]

• All tests are complete and pass the criteria
• The software meets all functional and non-functional requirements
• Obtaining approval from all relevant stakeholders
• Resolving all defects and issues identified during testing
• Documentation is complete and up-to-date

I will do "release acceptance testing" and "documentation".

[michaelchin]

do the following things before announce the new release

• make sure all the Jupyter notebooks work without errors.
• make sure the DEV warnings are not showing, especially the first big one.
• check the version number is correct.
• make sure the docker images work correctly.
• check the online documentation for errors.
• run pytest against all testcases.
• check pip installation on Windows, macOS and Ubuntu.
• check conda installation on Windows, macOS and Ubuntu.
• check all gplately commands work as expected.
• check the list of plate models is documented correctly.

[michaelchin]

The guidelines have been put at here. End of discussion.