Switch to explicit impl for redeclared events

The failing test from the previous commit causes the following metadata
to be emitted:

    .property instance class [mscorlib]System.Action`1<bool> Property()
    {
        .get instance class [mscorlib]System.Action`1<bool>
                         Castle.Proxies.IDerivedProxy::get_Property()
    }

    .property instance class [mscorlib]System.Action Property()
    {
        .get instance class [mscorlib]System.Action
                         Castle.Proxies.IDerivedProxy::get_Property()
    }

Obviously we need to switch to explicit implementation for one of these
events in order to avoid a name collision. We do that by changing the
"collision detection" such that it does not take into account events'
return types; only their name matters.

Author: stakx

src/Castle.Core/DynamicProxy/Generators/MetaEvent.cs

@@ -128,11 +128,6 @@ public bool Equals(MetaEvent other)
 				return true;
 			}
 
-			if (!Type.Equals(other.Type))
-			{
-				return false;
-			}
-
 			if (!StringComparer.OrdinalIgnoreCase.Equals(Name, other.Name))
 			{
 				return false;