Gets the prefix for a
resource's nested URL (e.g., prefix/collectionname/1.xml) This
method is regenerated at runtime based on what the prefix is set to.
# File activeresource/lib/active_resource/base.rb, line 338
def prefix(options={})
default = site.path
default << '/' unless default[-1..-1] == '/'
# generate the actual method based on the current site path
self.prefix = default
prefix(options)
end