* Added: the `import_mime_types_{...}` filter that receives the array holding allowed MIME types so that the user can add custom MIME types for the imported files.
* Fixed a bug that the screen icon could not be retrieved when the `strScreenIcon` key was not set (started to occur around v2.1.6).
- Changed the version to 2.1.7.
- Removed a debug log line.
Added the date in a change log entry.
- Changed the version to 2.1.7.1.
- Fixed a bug of checking existence of a class with the wrong name.
- Fixed a method to resolve src string to check if the given value is null.
Fixed a bug that the color field type was replaced with the taxonomy field type and the taxonomy field type was not available.
* Added: an example of basic usage of creating a page group as well as specifying a dashicon.
* Added: the ability for the `setRootMenuPage()` method to accept `dashicons`, the `none` value, and SVG base64 encoded icon for the second parameter.
Added the date in the newest entry of the change log.
* Fixed: the warning: `Strict standards: Declaration of ... should be compatible with ...`.
* Fixed: a bug that the `for` attribute of the `label` tag was not updated in repeatable fields.
Added a date to the latest change log item.
Merge branch '3.0.0b'

Conflicts:
	class/admin-page-framework.php
Adding the license text that could not be merged in the last commit.
- Added a description.
- Added a old change log of a diverged version (v2.1.7.2).
Removed an extra white space.
Fixed a bug that taxonomy fields caused the fatal error, "Fatal error: Cannot use object of type AdminPageFramework_Message as array in {...}"
Applied the changes to the minified version.