use UP1_HOST, UP1_APIKEY environment variables
use UP1_HOST, UP1_APIKEY environment variables

upclient now reads the UP1_HOST and UP1_APIKEY environment variables to
specify the host and api key instead of the hardcoded defaults. The host
can have a format of:

    "https://up1.example.com:8001"

Plain "http" is not supported, yet.

Partially addresses issues #1 and #2

Upload/upclient,lathan/upclient