Fix #283: don't print first arg of constructor
This changes the exception error message of a bad-arguments error to
suppress the constructor argument when the failure is a constructor.
This changes both the "Invoked with: " output to omit the object
instances, and rewrites the constructor signature to make it look
like a constructor (changing the first argument to the object name, and
removing the ' -> NoneType' return type.
diff --git a/example/issues.ref b/example/issues.ref
index 58cc798..0386d2c 100644
--- a/example/issues.ref
+++ b/example/issues.ref
@@ -18,3 +18,9 @@
PyA.PyA()
PyA.f()
In python f()
+StrIssue.__str__ called
+StrIssue[3]
+Failed as expected: Incompatible constructor arguments. The following argument types are supported:
+ 1. example.issues.StrIssue(int)
+ 2. example.issues.StrIssue()
+ Invoked with: no, such, constructor