Update assets.js: init fix, jaws.log functions

[videlais]

Changes: -- Fixed for jaws.init unit testing

-- Fixed useConsole to use_console and useLogElement to use_log_element to match style guide.

-- Added jaws.log.on (default true) for turning logging on and off.

-- Added jaws.log.error, which writes to console.error (if it exists, use_console is true, and log.on is true) or calls jaws.log with string "[ERROR]" + argument

-- Added jaws.log.warn, which writes to console.warn (if it exists, use_console is true, and log.on is true) or calls jaws.log with string "[WARNING]" + argument

-- Added jaws.log.info, which writes to console.info (if it exists, use_console is true, and log.on is true) or calls jaws.log with string "[INFO]" + argument

-- Added jaws.log.debug, which writes to console.debug (if it exists, use_console is true, and log.on is true) or calls jaws.log with string "[DEBUG]" + argument

-- All internal testing of function arguments now use the additional jaws.log functionality

[videlais]

Opps. That should read "core.js" instead of "assets.js". I have changes for that too and I was looking at the file as I was typing just now.