start on accounts using site context, improved settings page, clean up space representation

ext/numeric.rb

@@ -1,5 +1,15 @@
 class Numeric
+  ONE_MEGABYTE = 1048576
+
   def roundup(nearest=10)
     self % nearest == 0 ? self : self + nearest - (self % nearest)
   end
-end
+
+  def to_mb
+    self/ONE_MEGABYTE.to_f
+  end
+
+  def to_space_pretty
+    "#{(self.to_f / ONE_MEGABYTE).round(2).to_s} MB"
+  end
+end