Updated how API loading works

Instead of relying on loadAPI to populate the environment, it's less magic to just have loadAPI return the api object. All scripts loading APIs have been updated to match this.

This solves damien/cc-scripts#8, and works towards damien/cc-scripts#10.
Generalized repo URL to make testing forks easier
Made api objects stringify nicely
Generalized paths ready for API loading
Implement API autodownloading

Continuation of damien/cc-scripts#10
Renamed `loadAPI` to `api.load` for consistency with other functions
Removed installer api - part of damien/cc-scripts#12

The cc_scripts module now handles downloading files (to make bootstrapping easier)
Fixed minor error introduced in startup
Made the bootstrap more bootstrapped

Now downloads /api/cc_script/, and delegates installation to that.
Restart no longer required.
Fixed regression in direction API.
Use this repos url
Update move.lua

Fixes incorrect indices
Rename move.lua to mov.lua

move is a reserved name
Create itemset.lua

A library to make inventory management with computercraft turtles more straightforward
Adds a simple program to chop down redwood trees, possibly
First attempt at making common turtle-patching code
Rewrites turtletracker to use the patcher
Patches the turtle to allow things to handle fuel running out
Fixes use of obsolete API calls