* vm_trace.c: add `script_compiled` event. This event invoked
  after script compiling and before evaluating compiled script.
  Also the following methods are added:

  `TracePoint#compiled_instruction_sequence` method to get compiled
  `RubyVM::InstructionSequence` instance.

  `TracePoint#compiled_eval_script` method to get compiled script (String)
  by *eval methods (return nil if compiling by file).

* vm_trace.c (tracepoint_attr_raised_exception):


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66249 b2dd03c8-39d4-4d8f-98ff-823fe69b080e