Nicer Launchpad upstream releases with lp-project-upload

A while ago I introduced a script lp-project-upload to automate tarball release uploads to Launchpad.

Many people asked for further features, two of which I added now: First, it automatically invokes gpg to create a tarball signature (unless one is already present), and second it invokes an editor to specify changelog and release notes (just keep the files empty if you don’t need them).

Uploaded to lucid’s ubuntu-dev-tools, enjoy!