Enhance refresh method to overwrite options

[vishnukvmd]

There are use cases where in after initializing the widget, we need to alter the uploadUrl.
For example, if the URL is a function of the selected file type.

This PR essentially adds a setter for this variable. Can be accessed as follows:

$('#input').fileinput('setUploadUrl', url);

[kartik-v]

Have you tried using the refresh method:

$('#input').fileinput('refresh', {uploadUrl: 'your-url'});

[vishnukvmd]

@kartik-v Yes, but this does not update the URL. It continues to upload it to the URL that was initially set.

[kartik-v]

I have changed the title of this issue to offer a more generic approach to achieving such need and will update with an enhancement.

[vishnukvmd]

Yes, having a generic way to update all configuration parameters would definitely be better than this. Thanks.

[kartik-v]

Resolved via updates to release v4.4.4.