Fetch plugin: more fixup the fetch plugin

 - $fetch_timeout config option added
 - show error msg for image mimetype using gd functions
 - check $formatter->refresh
 - return retval correctly
 - use set_time_limit(0)
 - enable macro [[Fetch(url)]]
ShareButtons macro plugin added
fixup AsciiMathML processor for IE
fix for IE10/IE9
disable wikiwyg by default
fix for the MathJax

reset fontfamily and fontcolor for the MathJax cases
release 1.2.1