Improving tags for docker images

[diemol]

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Description

This PR addresses issue #992

Browser images will be tagged like this:

# Current tagging convention, kept for backwards compatibility
selenium/standalone-chrome              4.0.0-alpha-6-20200720
# Short browser version
selenium/standalone-chrome              84.0                                  
# Short browser version and build date
selenium/standalone-chrome              84.0-20200720               
# Short browser version, short browser driver version
selenium/standalone-chrome              84.0-chromedriver-84.0 
# Short browser version, short browser driver version plus build date
selenium/standalone-chrome              84.0-chromedriver-84.0-20200720
# Verbose tag (Short browser version, short browser driver version, grid version plus build date)
selenium/standalone-chrome              84.0-chromedriver-84.0-grid-4.0.0-alpha-6-20200720                   
# Browser version
selenium/standalone-chrome              84.0.4147.89  
# Browser version and build date
selenium/standalone-chrome              84.0.4147.89-20200720
# Browser version and browser driver version
selenium/standalone-chrome              84.0.4147.89-chromedriver-84.0.4147.30
# Browser version and browser driver version plus build date
selenium/standalone-chrome              84.0.4147.89-chromedriver-84.0.4147.30-20200720
# Verbose tag (Browser version, browser driver version, grid version plus build date)
selenium/standalone-chrome              84.0.4147.89-chromedriver-84.0.4147.30-grid-4.0.0-alpha-6-20200720   

Motivation and Context

To make the docker images tags more verbose, with that, users can easily see what versions are included in each image.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.