kgio 2.9.0 - cleanups, bug fixes, minor improvements

This adds a new kgio_syssend method for Ruby 1.9+ which behaves
like BasicSocket#send, but will not raise exceptions on EAGAIN.

Eric Wong (12):
      test_poll: remove race prone test_poll_EINTR_changed test
      tryopen: remove RARRAY_PTR usage in init
      read_write: remove the rest of RARRAY_PTR usage
      my_writev: stylistic fixes
      Rakefile: kill raa_update task
      avoid downsizing casts
      connect: constify RSTRING-related things
      set RSTRING_MODIFIED where appropriate for Rubinius
      split read_write.c into {read,write,writev}.c
      add kgio_syssend method to wrap send(2)
      write: correct check for various blocking regions
      tryopen: additional debug information for bad Errno values

Hleb Valoshka (1):
      Don't use deprecated api