Merge pull request #123 from Wobbo/master

Given the shell some love. (set and unset for env vars)
made io.stderr an extra stream that applies a red foreground color (if possible); writing errors to stderr in programs; quoting and escaping vars in list displayed by set.lua
resolving relative paths in PATH based on current working dir
checking for changes in tool slot in all activation cases now, fixes #124
copied license files to repo root for visibility
fixed flipped doc in screen
moved process management from shell to kernel and exposing it via new `process` api, removes some nasty cross dependencies
synchronizing filesystem component and making open/read/seek/close limited direct calls, reduced default max read buffer in turn. this should give better performance when reading many small files; made fs.close direct without limit to get rid of the ugly file handle gc workaround involving a timer
some cleanup; moved language specific file system (lua/rom) to lua architecture
Added positional parameters
fixed file system labels not being saved. oops.
Merge remote-tracking branch 'origin/master'
Merge remote-tracking branch 'upstream/master'