Misc. Binaries for v2.0.0-beta

Corresponds to v2.0.0-beta.

Adds binary for:

* Windows x86 and x64.  
* Linux x86.
  * Built on CentOS 5.11 with GCC 4.4.7 and glibc 2.5.
  * Credit goes to @mgreter based on:
    https://github.com/sass/node-sass/pull/516#issuecomment-67990558.

/cc @andrew, @keithamus