Release version should be point to defined GE version

[thimmy687]

Since this plugin is now no longer part of the main project and the main project is changing from version to version, the releases should point to a detailed supported version, like e.g. v3.3 or at least a concept is required to assure that the plugin is still working.

Maybe we need to release for each GE version a checked GerritPlugin version or sth. like this

https://github.com/gitextensions/GitExtensions.GerritPlugin/blob/master/src/GitExtensions.GerritPlugin/GitExtensions.GerritPlugin.csproj.user

[maraf]

I think the general idea is to always target latest stable release of Git Extensions.