Allow freestyle date entry

[machawk1]

The idea is such: If there is a massive amount of data (i.e., mementos), selection is difficult/awkward/cumbersome for the user. Currently we support dropdown (not scalable) and Miller columns. By providing a text input field where a user can enter any abbreviated date (e.g., "2014", "Jan 5", "2012 January", etc) with conversion support for a fuzzy date resolving library (e.g., moment.js), we might be able to make the selection of a memento a little more elegant.

Ext.js provide the Combobox UI element but this require a more abstracted data set in terms of datetime lookup. http://docs.sencha.com/extjs/5.1/5.1.0-apidocs/#!/api/Ext.form.field.ComboBox