fixes JOO-62
http://jangaroo.myjetbrains.com/youtrack/issue/JOO-62
joo.loadStyleSheet() only works for 31 style sheets in IE

As a special case for IE, using conditional JScript code, we
record all joo.loadStyleSheet() calls and "flush" every 31
style sheets and at the very end of jangaroo-application.js
by creating a <style> element with an @import directive for
every recorded style sheet.
Note that if not using the Maven build process that generates
jangaroo-application.js and using joo.loadStyleSheet(), you
have to call the new function joo.flushStyleSheets() manually
to make joo.loadStyleSheet() work in IE (even for less than 31
style sheets)!