* Move rand.h and rand.c to common directory and add most of RNG API from nist-branch
* Try to fix continuous integration errors
* Try fixing compilation bug on Windows
* Copy common.h and common.c from nist-branch
* Add OpenSSL PRNG if OpenSSL enabled
* Move common files around to match locations in nist-branch
* Add OpenSSL include to common build
* Only do prettyprint check on some Travis builds to shorten runtime
* Reorganize some files
* Missing variable in Travis config