test for reserved keywords with @ prefix
Merge pull request #39 from drslump/feature/override-parser-keywords

Extended the type/member normalization step to undo @ prefixes for reserved keywords
Explicit cast to IDictionary to retrieve the correct enumerator

The generic Dictionary<TKey,TValue> implementation also implements
IDictionary. Under the covers it uses explicit interface implementations
to return a different IDictionaryEnumerator for GetEnumerator()
depending on how it's accessed. The Boo.Lang.Hash class uses a generic
dictionary internally for its data structure, and has an excplicit
interface implementation for IDictionary.GetEnumerator(), but doesn't
subsequently cast the private dictionary to IDictionary as well,
resulting in the incorrect IDictionaryEnumerator being returned.

The result is any callers doing something like:
foreach (DictionaryEntry entry in myBooHashVariable)
{ }
will throw an InvalidCastException, as the enumerator for
Dictionary<TKey,TResult> returns a KeyValuePair<TKey,TValue> and not a
DictionaryEntry.

Simply "continuing" the excplicit cast to IDictionary returns the
correct enumerator.
Merge pull request #41 from aaronlerch/master

Explicit cast to IDictionary to retrieve the correct enumerator
Use Boo.Lang.Compiler.Ast.ExceptionHandler explicitly.
It conflicts with System.Reflection.Emit.ExceptionHandler in .NET 4.5
Merge pull request #42 from mausch/master

ExceptionHandler conflict
Merge remote-tracking branch 'upstream/master'