Needed to add assetmanger 0.1.2 hardcoding to devDependencies as well
#536 use required instead of validate for simple existence check
dependencies need only be in one group

`assetmanager` does not need to be under both `dependencies` and `devDependencies`. Removed from the latter.
Merge branch 'master' of https://github.com/linnovate/mean
delete users package