A Couple Dragons!

This is probably the last release before 3.0. Made a small change to the sass_interface.h file, requiring a source_string in the sass context.

• Lot's of fixes to compressed output (@xzyfer)
• New -V option to sassc (@jlinton)
• Maps now far more robust (@xzyfer)
• Whitespace fixes (@xzyfer)
• map-remove() function fix (@xzyfer)
• color name fixes (@SparkyBluefang)
• css-filter names now supported (@benesch)
• "----" interpolant bug fixed (@carsonmcdonald)