Rename skeleton.[ch] to net.[ch]

Also renames remaining references of Net Skeleton to Fossa
Fix handling of incorrectly encoded URIs
Merge pull request #44 from cesanta/fix_url_decode

DO NOT MERGE YET: Fix url decode
Merge pull request #118 from cesanta/kill_skeleton

Rename skeleton.[ch] to net.[ch]
Added mqtt broker ack cmds, ping/pong cmds, and fixes ns_mqtt_suback

Added and fixed unit tests.
Added --rm flag to docker so that it disposes of container after build.