Improve Search

[cignoni]

• Search should work also with sub-part of words (searching toroid should return also supertoroid filter)
• Search should allow two word query (in AND by default) so that if I write color quality it returns the filter that map color into quality.

[GMDIT]

• Search now work also with sub-part of words (searching "tor" return "Create Super Toroid" and "Create Torus")
• Search now allow multi word query, only in AND ("color quality", or "quality color" return "Generate Color from Quality")