v1.4.3

Changelog:

• Require /proc mount for new eopkg mechanisms
• Eliminate some unnecessary error / nil checks.
• Uses a native go HTTP downloader.
• Implements a new --image / -i flag on solbuild delete-cache command. This will delete stored main and unstable images, making removal of them easier.
• Changes image URI to https://packages.getsol.us/solbuild