Manual merge from old Akujin/Emergence plus new changes made to the main branch for namespaces.

-Includes a tool to import zip into the Emergence file system for an
empty site from CLI
-Includes a tool to erase a site's Emergence file system from CLI
-Added a custom error handler option for most DB functions to allow
custom handling for SQL errors. This allows features like automatic
table creation by ActiveRecord if a table is not found.
-New Emergence namespace for all classes
-EmergenceIO class now automatically detects if it's running in a CLI
and will write progress to CLI.
-PSR-0 autoloader support for the class loader in Site class.
-SiteFile will now throw better errors when Site::$rootPath is not
writable.