Stable version for EasyAdminBundle 2.x

tweak(doc): add migration doc
tweak(doc): update list override code
tweak(doc): add new overriden types
tweak(doc): typo
tweak(doc): add a specificity on ACL doc to explain that its still av…
tweak(doc): update image to match EasyAdmin 2 new layout
tweak(css): fix responsive for translations action
tweak(doc): update doc to match EasyAdmin 2.x
tweak(Design): upgrade to EasyAdmin 2.x
tweak(Design): upgrade DOM to match Bootstrap4

Assets 2