Add bookmark. Add feature: multiple tag selection.
Improved semantics >>	modified:   format.xsl
Show total number of tags and bookmarks >>	modified:   script.js
Improved tags presentation >>	modified:   style.css
Add multiple selection operators >> modified:   script.js
Tag tools section >>	modified:   format.xsl
Tag tools section >>	modified:   style.css
Updated completed tasks >>	modified:   TODO.txt