Show error message that ex constructor is broken with enforced keys

v0.3.1

Further clarify documentation

Use defoverridable for hooks, improve docs, add strict_keys option

v0.3.0

Add note about strict_keys with ExConstructor

Optimisations, rename success hooks

v0.2.0

6SFixed description

Added some documentation

v0.1.2

Bump version

Documentation fixes

0.1.1

Fixed documentation