Keep max_length when converting TextField to CharField in ModelSerializer

[tysonzero]

When Django makes a ModelForm out of a Model it validates the max_length of any TextFields (if specified) even though it is not enforced on a database level. I realize this did not use to be the case and that may be why DRF does not currently do the same with ModelSerializers. I see no downside to having them do the same. Currently TextField(max_length=1000) becomes CharField(style={'base_template': 'textarea.html'}).

[tomchristie]

Seems valid.

[jpadilla]

Working on this.

[tysonzero]

Awesome thanks!