1. How to get columns?
2. Your docs say: http://sheetsu.com/apis/12345/column/:column_name
Is ':' a documentation convention somewhere that I've not come across? I tried:
http://sheetsu.com/apis/12345/column/:Email
http://sheetsu.com/apis/12345/column/:email
until I realised it was just: http://sheetsu.com/apis/12345/column/Email