updated copyright years
"optimist" is a dependency, not only devDependency

fixed package.json
created a main module, returned by require('apl')
command-line compiler emits actually runnable code

If you compile a.apl like this:
    apl -c a.apl
a file named a.js will appear and you can run it with:
    node a.js
or
    chmod +x a.js
    ./a.js
incremented version