make ref x bindings produce region ptrs and fix various minor bugs

we now detect inconsistent modes, binding names, and various other errors.
typeck/trans integration is mostly done.

borrowck not so much.

more tests needed.

src/test/compile-fail/resolve-inconsistent-binding-mode.rs

@@ -0,0 +1,41 @@
+enum opts {
+    a(int), b(int), c(int)
+}
+
+fn matcher1(x: opts) {
+    alt x {
+      a(ref i) | b(copy i) => {} //~ ERROR variable `i` is bound with different mode in pattern #2 than in pattern #1
+      c(_) => {}
+    }
+}
+
+fn matcher2(x: opts) {
+    alt x {
+      a(ref i) | b(i) => {} //~ ERROR variable `i` is bound with different mode in pattern #2 than in pattern #1
+      c(_) => {}
+    }
+}
+
+fn matcher3(x: opts) {
+    alt x {
+      a(ref mut i) | b(ref const i) => {} //~ ERROR variable `i` is bound with different mode in pattern #2 than in pattern #1
+      c(_) => {}
+    }
+}
+
+fn matcher4(x: opts) {
+    alt x {
+      a(ref mut i) | b(ref i) => {} //~ ERROR variable `i` is bound with different mode in pattern #2 than in pattern #1
+      c(_) => {}
+    }
+}
+
+
+fn matcher5(x: opts) {
+    alt x {
+      a(ref i) | b(ref i) => {}
+      c(_) => {}
+    }
+}
+
+fn main() {}