Updates for Accessibility Test Framework v4.0.0:
- New check in AccessibilityCheckPreset.LATEST for issues related to font scaling issues
- New check in AccessibilityCheckPreset.PRERELEASE for unexposed text
- Improved heuristic text contrast checking using text character locations
- Removed obsolete *ViewCheck classes
- Updated dependency versions

 - Add 'suggestions' subpackage, providing programatic fix suggestions for certain identified issues
 - Fix string packaging and resource resolution issue
 - Update dependency versions

* Change README to README.md

It will trigger GitHub's rendering for real markdown.

Signed-off-by: utzcoz <utzcoz@outlook.com>

* Add code blocks for code snippet

It will help to highlight code snippet.

Signed-off-by: utzcoz <utzcoz@outlook.com>

 - Modified packaging of strings as assets to accomodate internal and external builds
 - Improvements to foreground/background color extraction for text contrast
 - Other bug fixes, enhancements, and APIs

Accessibility Test Framework v3.1

Updates:
 - Added LinkPurposeUnclearCheck
 - Removed deprecated AccessibilityInfoCheck and related classes
 - Beta API supporting the asking and answering of questions to refine accessibility results
 - AndroidX migration
 - Bug fixes, API additions, and other enhancements

Major updates:
 - 'uielement' package for generic UI representation
 - 'checks' package and AccessibilityHierarchyCheck for consolidated evaluation logic
 - New check: ClassNameCheck
 - New check: TraversalOrderCheck
 - Localized result strings
 - Protocol buffer representations for UI hierarchy, results, and Android constructs
 - Build switched to gradle