Position non-sticky footer at bottom of viewport

-Fix footer height and position after datatables are populated/drawn
-Remove footer-padding css rule
-Remove unnecessary spacing on all applicable pages

views/claim_address.pug

@@ -132,5 +132,4 @@ block content
             fieldset.entryField
               label(for='signature') Signature
               input#signature.form-control(type='text', placeholder='Signature', maxlength='100')
-          button.btn.btn-primary(type='submit') Submit
-    .footer-padding
+          button.btn.btn-primary(type='submit') Submit