[development] node types should not be changeable, operations need hooks

[Peter Wolanin]

While I really appreciate the hard work that went into moving
user-defined node types into core, I think there is a problem that
needs to be addressed:  the ability of users to change the
machine-readable name of the node type.

First- a question.  What is the use case for this?  If I don't like
the name of a node type (e.g. 'story'), I can just create an
alternative.  Trying to account for the possibility that the name of
the type has changed (to me) makes the code look rather more
convoluted than necessary and seems to introduce the potential for
more bugs.

Allowing users to change the node type will potentially create
problems- for example with organic groups, where the names of "group"
types are saved in a variable and there is no hook to let the module
know they have been changed.

Also, the current code fails to update user permissions (which are
construced from the node type), if the name of the type is changed.

So, I propose that this be removed and alslo that a hook be created to
allow modules to act when a node type is deleted.

issue posting: http://drupal.org/node/77990