Re-executing scripts during a breakpoint is now supported.

*  Previously, if you were halted at a breakpoint, and then re-defined
the function you were breaking in, the definition would have moved in
memory, and you'd have a hanging IP, crashing the VM.
*  Now, the VM is unwound and aborted if any function on the callstack
is reloaded during a breakpoint.
*  The debugger is sent an assert message to notify, and upon receiving
the new codeblock notification, the breakpoints are re-applied, and if
valid, will be hit on the next update.