PageIndicatorView Versions Save

1. Migrated to androidx
2. Fixed issue with dynamicCout is not working after re-set ViewPager adapter

1. Added ability to hide PageIndicatorView while it is idle.
2. Updated build.gradle configuration compile to implementation.

1. Bug fixes

1. Added indicator click listener
2. Added new animation type SCALE_DOWN
3. Fixed issue with non working setProgress method if PageIndicatorView is not attached to ViewPager
4. Added new method to setSelected specific indicator without animation

1. Bug fixes and performance optimisation
2. Updated sample application

1. Added new orientation attribute to display indicator in HORIZONTAL or VERTICAL orientations.
2. Added new auto visibility attribute, to automatically hide indicator while in has <= 1 count.
3. Bug fixes.

1. Added new AnimationType.SWAP animation.
2. Added RTL support.
3. Fixed issue with restoring state.

Special thanks to @sannyo and @Andy671

1. Added restore instance state for selected page
2. Added new Drop animation type
3. Fixed issues with dynamic count
4. Fixed invisible view issues while creating PageIndicatorView from java code
5. General code clean up

1. Fixed possible IllegalStateException while un-registering viewpager's adapter data set observer
2. Fixed issue with redrawing circles after data set observer call
3. Fixed bug with not working dynamic count if set it (and viewpager id) as attributes
4. Renamed attribute 'dynamicCount' to 'piv_dynamicCount' to avoid name conflicts
5. General stability improvements

Minor fixes and code clean up