Complete Config-Map Documentation Overhaul
Complete Config-Map Documentation Overhaul

Changes the Config-Map documentation to be easier to search and follow
a format similar to that in the annotations section. Also adds some missing
configuration options.

Fixes #1532

kubernetes/ingress-nginx,caicloud/ingress,canhnt/ingress,caicloud/ingress,kubernetes/ingress-nginx,canhnt/ingress,danielqsj/ingress,aledbf/ingress-nginx,nicksardo/ingress,aledbf/ingress-nginx,caicloud/ingress,canhnt/ingress,aledbf/ingress-nginx,nicksardo/ingress,danielqsj/ingress,aledbf/ingress-nginx,nicksardo/ingress,canhnt/ingress,kubernetes/ingress-nginx,kubernetes/ingress-nginx,caicloud/ingress,nicksardo/ingress,kubernetes/ingress-nginx