Add vector indexing of ASCIIString

With this commit, now you can do this:
   s = "swap me"
   indx = [4,3,6]
   s[indx]

Author: timholy

jl/ascii.jl

@@ -9,6 +9,7 @@ ref(s::ASCIIString, i::Int) = char(s.data[i])
 ## overload methods for efficiency ##
 
 ref(s::ASCIIString, r::Range1{Int}) = ASCIIString(ref(s.data,r))
+ref(s::ASCIIString, indx::Array{Int,1}) = ASCIIString(s.data[indx])
 strchr(s::ASCIIString, c::Char) = c < 0x80 ? memchr(s.data, c) : 0
 strcat(a::ASCIIString, b::ASCIIString, c::ASCIIString...) = ASCIIString(memcat(a,b,c...))