Disallow assigning attributes on Rect class

[lordmauve]

Originally reported by: Daniel Pope (Bitbucket: lordmauve, GitHub: lordmauve)

---

Issue #11 "Cannot assign attributes on Rect object" was a bad idea.

I immediately hit a case where someone (@tjg) had written bat.centrex instead of bat.centerx - and this fails silently once again.

Now we have a spellchecker we could spellcheck this and fail with an appropriate error.

There's also a concern about incompatibility with Pygame itself - if users have been used to assigning attributes to Rect objects, it may cause confusion when using Rect objects from Pygame itself which do not allow this.

---

• Bitbucket: https://bitbucket.org/lordmauve/pgzero/issue/32

[lordmauve]

Original comment by Daniel Pope (Bitbucket: lordmauve, GitHub: lordmauve):

---

Disallow setting attributes on Rect; enrich corresponding AttributeError with spellcheck suggestions (closes #32)