Library associative array project v0.0.1

[Steven Schveighoffer]

I just spent a couple hours making a library AA solution that is binary 
compatible with druntime's builtin AA.

The benefits:

1. Proves that a library implementation is possible, also shows where 
shortcomings are.
2. Usable at compile time to make an AA that can be used at runtime.
3. Much more approachable code than the AA runtime, does not require 
"faking" a typeinfo, dealing with typeinfo in general, or deal with 
magic compiler hooks. This gives a good base to start experimenting with.

For the future:

1. Implement all the things that AAs can do (which are possible, some 
are not).
2. Look at alternatives to GC for allocation/deallocation.
3. Possible use with betterC?

Anyway, enjoy!

https://code.dlang.org/packages/newaa

-Steve