Simplified an unnecessarily complex paragraph in view docs
Fixed typo in multipartparser.py
Fixed #21798 -- Added check for DateTime mutually exclusive options

Added DateTimeCheckMixin to avoid the use of default, auto_now, and
auto_now_add options together. Added the fields.E151 Error that is raised
if one or more of these options are used together.
Fixed #21634 -- Prevented hiding ImproperlyConfigured when command not found

Thanks nikolay.v.golub@gmail.com for the report.