Merge pull request #1 from creuzerm/ui

Ui
Lib cleanup - moving to corresponding items to lib directory
Move functions out of index.php and into process.php
Include the include!
Tweaks to keep what was running, still running.
Merge pull request #2 from creuzerm/backend

Backend
Learning GIT, didn't include backend.php
Merge pull request #3 from creuzerm/backend

Learning GIT, didn't include backend.php
Fix for bad preview image.
Mods to UI: Email button, modal popups, button positioning,
introduction of logo image.
Moving image file (name)
Flushing out old png, disabling buttons - didn't work on server
Disabling email button until we have the functionality in
Updating gif, txt references to No 6/9. Updating CSS in ref to buttons.
Implementing loading modal, updating help and disclaimer content and
functionality
Language issue
Forcing preview tab on submit param in url
Hide email btn, hide preview tab when no submit, sample btn now below,
moving help btn
Updating look and feel for download STL link
Forcing 'Load data' to load wait state modal