More little bugs and suggestions from Engledogg:
- now showing a "File is too large" sort of error message *before* you upload that 130MB photo
- fixed issue where "0" would appear in the mold input box for parts with no molds
- fixed issue with cloning parts
- fixed page crash related to navigating to deeply nested nodes in the /view_lacks and /missing_info trees
Also:
- fixed appearance of the PRODUCT/PART tabs when viewing on mobile devices
- added the responsive icons to the same sprite resource as the other ones
- fixed /collectors page
