ECC code landing

[ian.m...@sun.com]

Tomorrow I will check in a large patch to NSS that extends the ECC
implementation from NSS 3.8. The new features of this code include:

* support for optimized curve-specific implementations
* optimized integer and floating point code for commonly-used named
curves
* supported for creating, importing, and exporting EC keys and certs
* server-side support for ECDH-RSA, ECDH-DSA and ECDHE-ECDSA key
exchange
* new scripts to automate testing of ECC support
* ECC support in command-line tools (certutil, pk12util, tstclnt,
selfserv)

This code will not be enabled by default. To build with ECC support,
use NSS_ENABLE_ECC=1 with the gmake command.

A big thanks to Sheuling Chang, Stephen Fung, Vipul Gupta, Nils Gura,
and Douglas Stebila of Sun Labs for making this contribution!

-Ian