LP#1622696 Prompt dialog format and promise repairs

LP#1622696 Prompt dialog format and promise repairs

Improve egPromptDialog formatting by wrapping the column div in a row
div.  This helps the text input site nicely in the middle of the dialog
without overlaps.

Allow for the creation of egPromptDialog without a user-defined scope.

Pass the result of an egPromptDialog to the dialog resolver in addition
to the optional user-defined scope.ok function.

The 2 above changes reduce the amount of boilerplate code required to
collect the dialog value.  For example:

egPromptDialog.open(msg, default_val).result
    .then(function(prompt_value) { ... });

Signed-off-by: Bill Erickson <berickxx@gmail.com>