change export not to perform full lookup

this is better behavior and also tends to reduce annoying error messages
about explicit importing.
fix imports/exports in cairo

examples/winston_tk.jl

@@ -1,10 +1,7 @@
 load("plot.jl")
 load("tk.jl")
 
-import Tk.*
-import Cairo.*
-import Winston.*
-import Plot.*
+using Tk, Cairo, Winston, Plot
 
 function TkRenderer(name, w, h)
     win = Window(name, w, h)
@@ -27,6 +24,6 @@ end
 
 function imagesc(I)
     h, w = size(I)
-    pl = imagesc((0,w),(0,h),I)
+    pl = Plot.imagesc((0,w),(0,h),I)
     tk(pl, w, h)
 end

extras/cairo.jl

@@ -30,6 +30,10 @@ export CairoSurface, finish, destroy, status,
     open, close, curve, polygon, layout_text, text, textwidth, textheight,
     TeXLexer, tex2pango, SVGRenderer
 
+import Base.get
+
+global fill, open, close, symbol
+
 try
     global _jl_libcairo = openlib("libcairo")
     global _jl_libpangocairo = openlib("libpangocairo-1.0")
@@ -72,7 +76,7 @@ end
 
 for name in ("destroy","finish","flush","mark_dirty")
     @eval begin
-        $(symbol(name))(surface::CairoSurface) =
+        $(Base.symbol(name))(surface::CairoSurface) =
             ccall(dlsym(_jl_libcairo,$(strcat("cairo_surface_",name))),
                 Void, (Ptr{Void},), surface.ptr)
     end

src/module.c

@@ -193,14 +193,10 @@ void jl_module_export(jl_module_t *from, jl_sym_t *s)
 {
     jl_binding_t **bp = (jl_binding_t**)ptrhash_bp(&from->bindings, s);
     if (*bp == HT_NOTFOUND) {
-        jl_binding_t *b = jl_get_binding(from, s);
-        bp = (jl_binding_t**)ptrhash_bp(&from->bindings, s);
-        if (b == NULL) {
-            b = new_binding(s);
-            // don't yet know who the owner is
-            b->owner = NULL;
-            *bp = b;
-        }
+        jl_binding_t *b = new_binding(s);
+        // don't yet know who the owner is
+        b->owner = NULL;
+        *bp = b;
     }
     assert(*bp != HT_NOTFOUND);
     (*bp)->exportp = 1;