add: build script for amcl.js
add: build script for amcl.js

miracl/milagro-crypto-c,milagro-crypto/milagro-crypto-c,milagro-crypto/milagro-crypto-c,philipp-cliqz/milagro-crypto-c,philipp-cliqz/milagro-crypto-c,philipp-cliqz/milagro-crypto-c,miracl/milagro-crypto-c,miracl/milagro-crypto-c,miracl/milagro-crypto-c,milagro-crypto/milagro-crypto-c,philipp-cliqz/milagro-crypto-c,milagro-crypto/milagro-crypto-c,miracl/milagro-crypto-c