Implement editing and searching tags

[GoogleCodeExporter]

I can't find any free tree-type not taking software that implements tags. There 
are many times when searching for a word brings up too many irrelevant results, 
so I'd like to have multiple tags per node, and be able to search and display, 
only nodes which contain that tag. 

thanks!

Original issue reported on code.google.com by [email protected] on 9 Apr 2014 at 12:34