Started appending the container require prefix to all require paths.
This commit includes the following related changes:

# Removed the leading forward slash from require paths as this actually
signifies a file path rather than an absolute require path as might be
expected.
# Made conformant BRJS code throw an exception if classes aren't
correctly namepaced as this would otherwise prevent us from having
require paths that are freely convertible to namespaced names.
# Updated all tests that created incorrectly namespaced classes.
Improved the failure message when assetLocationHasDependencies() is used
with an asset location that doesn't exist.
Minor whitespace improvement.