Use same context when creating a new context::Fraction::Parser::Number

When creating a context::Fraction::Parser::Number, use the same
context as the original object instead of the current context.

This fixes issue #1337 with checking if an object created in the
fraction context is equal to a number after the context has changed.
This fix is by @dpvc.

Author: somiaj

macros/contexts/contextFraction.pl

@@ -781,7 +781,7 @@ package context::Fraction::Parser::Number;
 
 sub new {
 	my $self = shift;
-	my $num  = &{ $self->super('new') }($self, @_);
+	my $num  = &{ $self->super('new', $_[0]->context) }($self, @_);
 	$num->setExtensionClass('INTEGER') if $num->{value_string} =~ m/^[-+]?[0-9]+$/;
 	return $num->mutate;
 }