open time picker above/below input field (according to position within viewport), see #242
Merge branch 'stable/2.4.x' of https://github.com/sehmaschine/django-grappelli into stable/2.4.x
new minified js, see #272
improved floledermanns quick-fix for mobile devices, see #270 and #274
improved styles for selecting month/year with date picker, see #251