hero header min-height, margin on alert, min-length before query

Adding a hero header to the min-height so that it doesn't look weird on a smaller screen (min-height 640px)
add the margin back in temporarily. closes #96
Cloak the select statement on page load, and show the selected crop
Merge pull request #107 from simonv3/style-tiles

hero header min-height, margin on alert, min-length before query