Add a DNSSEC tarball verification note from @jedisct1 in #51

download.libsodium.org vends DNSSEC-secured SHA256 hashes of release tarballs.
Merge pull request #52 from dsheets/patch-1

Add a DNSSEC tarball verification note from @jedisct1 in #51
libsodium.org is now available over HTTPS & SPDY
Prepare for a version bump.
Remove dead assignments that the compiler optimizes out.
Mark clang false positives
Remove -I/usr/local/include and -L/usr/local/lib
libsodium doesn't have any dependency on 3rd party libs.
Disable asm implementations when compiling to javascript with emscripten.
autoconf: start moving AC_ARG_ENABLE macros to the top of the script.
Add a pre-js script for providing /dev/urandom to tests in Javascript.
Not plugged to the build system yet.
autoconf: keep moving switches to the top of the file
autoconf: move the last switch, --enable-debug
Move --enable-pie switch
Document --disable-pie instead of --enable-pie
Don't -> Do not
Add a sodium_bin2hex utility function.
Use sodium_bin2hex() instead of duplicating the same code everywhere.
Update NEWS file
It's a fork.
Mention ocaml-sodium