ZAS / nucname.id() implemented and propagated through out the code base  

After (too) many months, I have finally implemented *the* canonical form for nuclide identification with 32-bit integers [which was discussed here](https://groups.google.com/d/msg/pyne-dev/XASCsR9JgWc/GYb6-CsOQ38J).  This is the ZZZAAASSSS format, which preserves sort order, etc.

Additionally, I have added `znum()`, `anum()` and `snum()` functions so that people don't have to remember the tedious constants that are required.  

This has a huge impact on basically all parts of the code base, but should have not performance impacts.  It is highly recommended that humans do not normally use this format, and instead pump input through the `id()` and `name()` functions.  This PR increases the generality of the `id()` function over the `zzaaam()` function.

An updated version of the `prebuilt_nuc_data.h5` file has been uploaded to S3.  This PR will required nuc_data to be rebuilt on all clients.