Proper panic

[MovingtoMars]

We should have a nice panic function that unwinds the stack, runs deferred functions, then prints a pretty error message with stack trace.

Right now, panic is temporarily implemented as a function in runtime.

[felixangell]

When you say its "temporarily implemented as a function runtime"... will it always be in the runtime? Me and @kiljacken discussed this in IRC, and we think that it might be best if its moved into the standard library so we don't have dependencies to libc in the runtime of the language.

[MovingtoMars]

To unwind the stack and all that stuff, it needs to be implemented in the compiler.

[felixangell]

As in, the runtime of the compiler?