Adding specs and changing #swf_tag to generate static embed HTML.

Also, swfobject.js has been renamed to swfobject.min.js and the
uncompressed version has been added, named swfobject.js. This follows
conventions set by jquery-rails.
Adding new info about #swf_tag to README
Merge branch 'master' of https://github.com/petebrowne/swfobject-rails into petebrowne-master

Conflicts:
	swfobject-rails.gemspec
	vendor/assets/javascripts/swfobject.js