add some validations

[ShowBaba]

add validations to some inputs like filename and file path (should contain a file extension), this might cause the file URL to be invalid

[opensaucerer]

True...let's also create a new bifrost error code called ErrInvalidParameters so we have something like

return nil, &errors.BifrostError{
	Err:       fmt.Errorf("the error message"),
	ErrorCode: errors.ErrInvalidParameters,
}

[opensaucerer]

Resolved