Merge pull request #38 from Uberi/master

Update Overview.html
Add vertical version of airtight pipe entry
if automatically rotates to connect to the thing you point at, if a connection
is possible.
added sunlight_propagates=true to most devices to fix lighting issues
adjusted size of spigot "pouring" segment.
Made spigot animated, so the water actually looks like it's pouring
more minor lighting/texture tweaks
new textures for spigot to support animated water + fix lighting issues
Added appropriate textures for mesecon conductor tubes
Made conductor tubes cheaper.
corrected yield on conductor tube crafting image