snapshot: support ip address literals, more docs - #403

control: job assigned to worker 01M4W965R7HQKQQ0G0T2EY7DRK [factory aws, i-0ae8c9f64aa8f0044] (queued for 30 s)
...
task: starting task 0: "setup"
task: process exited: duration 18183 ms, exit code 0
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task: starting task 1: "rust-toolchain"
task: process exited: duration 8126 ms, exit code 0
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task: starting task 2: "authentication"
task: process exited: duration 28 ms, exit code 0
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task: starting task 3: "clone repository"
task: process exited: duration 1176 ms, exit code 0
...
task: starting task 4: "build"
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|   # #    #####    #####     #    ######    ##     ####    #####   ####
|  #   #   #    #     #       #    #        #  #   #    #     #    #
| #     #  #    #     #       #    #####   #    #  #          #     ####
| #######  #####      #       #    #       ######  #          #         #
| #     #  #   #      #       #    #       #    #  #    #     #    #    #
| #     #  #    #     #       #    #       #    #   ####      #     ####
| 
| + sudo mkdir -p /out
| + sudo chown 12345 /out
task: process exited: duration 234582 ms, exit code 0
|W| found 4 output files
|W| uploading: /work/swadm (11256472 bytes)
|W| uploaded: /work/swadm
|W| uploading: /work/swadm.sha256.txt (65 bytes)
|W| uploaded: /work/swadm.sha256.txt
|W| uploading: /work/dpd (21388616 bytes)
|W| uploaded: /work/dpd
|W| uploading: /work/dpd.sha256.txt (65 bytes)
|W| uploaded: /work/dpd.sha256.txt