can be improved to support variadic notation (a..b..c..d) if detecting
type of octet on the right side and acting accordingly.

implemented and improved basic operations for ECP2 and FP12 with test
coverage for miller loop (ate + fexp).

for some yet undetected reason the msgpack library instantiates a
global table 'msgpack' with its own object even without assignation,
so we rename it and nil it in init.lua to avoid collisions.

install swig in travis' brew,
use gcc in place of ld for osx
always use CC for -shared linking of python modules

update also integration tests and iot examples

various language improvements to simplify packing/unpacking and
validation as well mapping simple conversion functions to table values

added high-level simple global functions to encrypt()/decrypt() which
execute KDF2 session and AES-GCM automatically by comparing headers.
Data format passed around is a table carrying the IV, header and checksum.

Also removed unuseful string tests: safe_string is now a local
function used internally, just checking for NULL or empty string.

There is still a problem when loading binary files where \0 may occur:
they get truncated when instantiated as Lua's string types. Should be
made octets directly.

also improved nodejs wrapper with hashbang and included examples
directory in distributed binaries.