Mitigating the attribute proliferation - attribute inference for functions

[Dicebot via Digitalmars-d]

I think point about `export` is important. Tying definition of 
"API" to `export` instead of `public` fits much better definition 
of those attributes (latter only guarantees symbol access, former 
also ensures cross-binary availablity) and allows for more 
explicit migration step (as `export` is widely underused right 
now).

Also the issue you have pointed out about API templates that call 
private functions is essentially same issue as Benjamin was 
pointing out here : 
http://forum.dlang.org/post/m9lhc3$1r1v$1@digitalmars.com

I can't propose good solution here right now but I do believe 
those 2 problems need to be solved in one step.