rust compiler now a runtime dependency.

[Mike Pumford <mpumford%mudcovered.org.uk@localhost>]

Just done a pkgin upgrade and I'm being asked to install rust as a 
runtime dependency which seems wrong.

According to pkgin:
pkgin show-deps librsvg
direct dependencies for librsvg-2.44.14
        rust>=1.20.0
        pango>=1.42.4nb2
        libxml2>=2.9
        libcroco>=0.6.5nb2
        glib2>=2.34.0
        gdk-pixbuf2>=2.34.0nb1
        freetype2>=2.8.0
        fontconfig>=2.13.0
        cairo>=1.16.0

No other rust compiled tools need this. Is there a reason why librsvg 
does? Its a big runtime dependency for a library.

Mike