Add ability to give non-admins access to the tag manager

[#1]

I would like to be able to create a group and give that group access to the tag manager even if they are not admins.

[#2]

An additional group for Digital Pulse would be great too!

[#3]

While we're talking granting access:

   only view access versus edit access

   only access to dev tags

   only access to dev/staging tags

   only access to Custom Code Modules

It's like user access was completely forgotten about in this product...