Support the Screen interface

(WindowImp::getScreen) : Add details
(ScreenImp) : Add details using glut
Support media query - step 1: Incorporate the media query syntax

src/css/CSSGrammar.yy, src/css/CSSTokenizer.re : Incorporate the media query syntax
(MediaListImp) : Refine for supporting media query parser
(CSSValueParser) : Refine for supporting media query parser
(CSSTokenizer) : Add MediaQuery mode
(CSSParserString::compareIgnoreCase) : New
(CSSMediaRuleImp::setMediaList, CSSImportRuleImp::setMediaList, CSSImportRuleImp::CSSImportRuleImp) : Refine
src/MediaFeatureNames.re (MediaListImp::getFeatureID) : New
src/MediaTypeNames.re (MediaListImp::getMediaTypeID) : New
Makefile.am : Add MediaFeatureNames.re and MediaTypeNames.re
Support media query - step 2: Switch over to Media Queries from Media Types in CSS 2.1

(MediaListImp::matches) : New to replace MediaListImp::hasMedium()
(HTMLLinkElementImp::refresh, CSSRuleListImp::append) : Refine using MediaListImp::matches()
(ScreenImp) : Add more utility functions for MediaListImp::matches().
(WindowImp::getScreenImp, WindowImp::getPx) : New
(ViewCSSImp::getDPI, ViewCSSImp::setDPI) : Remove; use ScreenImp::getDPI() if necessary
Merge branch 'master' of github.com:esrille/escudo

Conflicts:
	src/html/ScreenImp.cpp