Accept thousand separator in forms.DecimalField while USE_THOUSAND_SEPARATOR is False

[Mounir Messelmeni]

In many cases I find it useful that when using localize within a DecimalField for example to accept thousand separator from form/user input.

Turning USE_THOUSAND_SEPARATOR will mostly result in changing the display for numbers in all the project which in many cases does not make sense.

So the idea is to separate the settings to make it possible to turn this on only for user input but not for displaying it or adding an extra argument to DecimalField to accept input with thousand separators.

Of course a quick workaround would be to define a custom DecimalField and make it accept this but I still think it might make sense for users in general.