[bugfix] images url

mwcardex.js:
_my bad_, remove ABSOLUTE path for images
set font-size for select2

index_dev:
uses minified database
test appcache

 On branch gh-pages
 Changes to be committed:
	modified:   index_dev.html
	modified:   js/dev/mwcardex.js
	modified:   js/mwcardex.min.js