The following k8s versions are currently available for new clusteres in
EKS: 1.14 (can't deploy via AWS management console), 1.15, 1.16, 1.17,
so update the eks_cluster.yaml to support these versions and default to
1.16

Add k8s versions to form constants

Set default version to 1.16

Make default version an array

Remove unused imported variable

Add kubernetes version column to aws table

Add kubernetes version to cf parameters

Revert "Add kubernetes version to cf parameters"

This reverts commit 6032881714103a7c7007fce63fea6d260accd0ac.

Fixing failing jest and rspec

Use text instead of string

Add text limit to db

Change table name back

At some point I'd changed the table name to singular which was breaking
spesc, so change name back. Also use string in column, disable prevent
strings

Add kubernetes version to request payload

Move k8s version within provider attributes

Remove unused migration

I added an extra column because pg was complaining, but now that I've
moved the parameter there is no longer an undefined table error so
remove the unused column

Remove trailing blank line

Remove unwanted db changes