core plugin version checking does not support explicit versions or prereleas

Itr just uses the specified version as a min version - would be good to be able to specify specific versions, including prerelease

one reason it woul dbe good to specify an specific version is to test the upgrade process - currently the latest version is always taken. Instead, would be good, after publishing 1.1, to specifiy 1.0, install it, then specify 1.1 and verify the upgrade works