Add more controls for more.lua command + tidy up

Added more keys for the command to recognise ("page down" goes to the next page in the same way as "space", "enter" and "down" print just the next line)
Moved the code to print lines from the file to a function to reduce the space used by repeating it for the new keys
Merge remote-tracking branch 'upstream/master'
Fix problem pointed out by fnuecke

Changed 1 and 0 to true and false
Merge git://github.com/jamesb6626/OpenComputers
Minor cleanup to more.lua, fixed single line advance to not exit when at end of file.