WARNING

this release is the first release using androidX, stay with older versions for pure appcompat dependencies
in addition it has completely reworked items and headers using the new android constraintlayout v2.0.0-alpha2

Changes

add new dependency, constraintlayout
- constraintLayout 2.0.0-alpha2 to be able to use MotionLayout
add migration info for new theme attributes
reflect changes in README
re-model all included drawerItems to have a more flat hierarchy by using constraintLayout, simplify them as far as possible
introduce new util method themeDrawerItem which will apply the selected item design according to the material design guidelines (1 and 2)
support disabling material 2 design via theme
re-work the headers to use a ConstraintLayout and hugely simplify the layout hierarchy