[ANN] sexp_processor 4.9.0 Released

sexp_processor version 4.9.0 has been released!

* home: <https://github.com/seattlerb/sexp_processor>
* rdoc: <http://docs.seattlerb.org/sexp_processor>

sexp_processor branches from ParseTree bringing all the generic sexp
processing tools with it. Sexp, SexpProcessor, Environment, etc... all
for your language processing pleasure.


### 4.9.0 / 2017-04-13

* 9 minor enhancements:

  * Added Sexp.depth
  * Added Sexp.sexp_type=
  * Cache Sexp.line_max. Massively speeds up large flay runs.
  * Cleaned up SexpProcessor.process handling of result node type.
  * Extend pt_testcase for ruby 2.4 tests.
  * Extended Sexp.method_missing to only print on every invocation if $VERBOSE=1
  * Extended Sexp.method_missing to warn if the expected sub-sexp is not found.
  * Rewrote Sexp.mass to be MUCH faster. Helps tremendously with flay on large files.
  * Warn that Sexp#method_missing was tripped if $DEBUG.