Transitions to new language semantics

[zjh]

We have `enough features` in D.
But, one have to use `d` carefully in production,since it is not 
stable enough.
We need a stable D version. Then gradually experiment.
Rather than only the latest version one. Although the development 
is fast, there are a lot of bugs. This scares away beginners.
I think after D teams finished `ImportC`, we should first create 
a stable version.
This stable version lasts for 2 years, mainly fixes bugs.
And the new and latest version, `d team` can do `BIG change`. 
Anyway, we have a stable one available.
In my opinion, the `Big change` is to divide large files into 
small files, so that the granularity of source files is smaller 
and the dependency relationship is clearer. By the way,solving 
the problem of GC .So it's less likely to have fatal errors.
This way,many people would like to join `the d development`.