New build.xml, fixes crashes/exceptions

Reverted folder structure to match the package structure. /buildcraft/additionalpipes/...

Updated build.xml based on the one used by LogisticsPipes -- automatically download and set up mcp/forge, and stage the buildcraft source for build 130 (files stored on my azure website -- please contact me for arrangements for long-term use)
A better way to implement #49 

Fixed NPE when loading localization for the item friendly names, restructured the folder structure to match buildcraft, removed a redundant check when loading the language -- buildcraft already does this

Fixed unhandled exception when the server started on buildcraft dev builds - new api change after the 3.5.1 release.

The previous two fixes address #50