create: punt on bad URLs

When we can't detect a name from the URL, just ask the user.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Library/Homebrew/cmd/create.rb

@@ -20,7 +20,7 @@ module Homebrew extend self
           :autotools
         end
 
-        if fc.name.to_s.strip.empty?
+        if fc.name.nil? or fc.name.to_s.strip.empty?
           path = Pathname.new url
           print "Formula name [#{path.stem}]: "
           fc.name = __gets || path.stem
@@ -67,7 +67,7 @@ class FormulaCreator
     path = Pathname.new url
     /(.*?)[-_.]?#{path.version}/.match path.basename
     @name = $1
-    @path = Formula.path $1
+    @path = Formula.path $1 unless $1.nil?
   end
 
   def version