Uses entrypoint and exec to launch redsocks wrapper script

Entrypoint allows us to pass arguments easily, and exec allows the console to respond to ctrl+c
Allow setting both http and https proxies at the same time

Most upstreams are http/https on the same port. Allow the user to set this by using the first argument. This
results in less typing when using redsocks. Will only set http_proxy and https_proxy if undefined, so environment
variables take precedence over this change
Merge pull request #1 from btrepp/entrypoint

Allow arguments to be supplied to run command