Adapt RDF term symbol
Add turtle or ttl related icons
Add file related icon named turtle
Fix TTL icons
Delete obsolete turtle files
Add flamboyant icons for instance and class
Merging
Merge https://github.com/k00ni/semicon

Conflicts:
	README.md
	downloads/semicon.tar.gz
	downloads/semicon.zip
	png/all/32/rdf.png
	png/terms/32/rdf.png