Remove node.js mention about discouraging specific versions

One of the customers asked about this sentence, ie. if older versions get removed. I think this is misleading, because even if we remove one of the older versions, it will still be compiled, so while it may increase the build time, it should work correctly, at least to some degree (really old versions may have problems with compiling).

I've changed this part to encourage specifying major and minor version only, but without "highly discouraging" doing otherwise.