Adjust table header alignment on editing/completion

 - took advantage of existing ‘editing’ property on view controllers
 - moved a couple of methods into controller to avoid exposing tableview
Increase opacity of header

 - to avoid distracting level of “bleed through” of underlying cell
contents
Animate header slide to match cell contents slide
Fixed a couple warnings
Addressing review comments
Merge pull request #36 from fightingwalrus/igcs-81-mission-planner-edit-align

Igcs 81 mission planner edit align