Added FleetingFilesystem to get around twig's internal cache.
Moved the bulk of Compiler::build to Compiler::buildFile to add additional flexibility.
Added FileUtils::getFileModifyTimes to allow for watch functionality.
Added watch command.
Updated FileUtils::getFileModifyTimes to use php 5.3 compatible syntax.
Merge pull request #30 from puritysdisciple/master

Added watch command.