V2 string

[Derek Parnell]

I'm converting Bud to compile using V2 and so far its been a very hard
thing to do. I'm finding that I'm now having to use '.dup' and '.idup' all
over the place, which is exactly what I thought would happen. Bud does a
lot of text manipulation so having 'string' as invariant means that calls
to functions that return string need to often be .dup'ed because I need to
assign the result to a malleable variable. 

I might have to rethink of the design of the application to avoid the
performance hit of all these dups.

-- 
Derek Parnell
Melbourne, Australia
skype: derek.j.parnell