uninstall script get rid of drop cascade

[robe]

Can we please get rid of the drop cascade in the uninstall scripts. I was testing and accidentally installed postgis in the wrong schema. When I went to fix the error by using the uninstall script, I blew out all my geometries.

Needless to say I'm a bit irked.

[robe]

Came across someone on IRC who was about to do this. So I'm not the only one who makes this fatal mistake. If we are going to be destroying people's data, I really think we should at least warn them about it. Especially for 2.0.

[strk]

Robe: we can't get rid of drop cascade for types due to circular dependencies: type requires input/output functions while output function needs type. Unless you handle to solve the puzzle the best we could do is add a check for the presence of tables requiring the type (and excluded the ones we install ourselves). Doesn't seem like an easy task, anyway.

[pramsey]

Yeah, you're not really uninstalling if you're keeping your data.