Remove packagemaker code, use productbuild to generate .pkg

git-svn-id: https://svn.code.sf.net/p/rubycocoa/svn/trunk/src@2459 f4f36d40-9719-0410-9868-dde021a23eda
Refactor ruby-2.0 rename symbols

define rename symbols in internal_macros.h.
- ruby_errinfo -> rb_errinfo
- is_ruby_native_thread -> ruby_native_thread_p
- rb_frame_last_func -> rb_frame_this_func

git-svn-id: https://svn.code.sf.net/p/rubycocoa/svn/trunk/src@2460 f4f36d40-9719-0410-9868-dde021a23eda
Fix syntax error of standaloneify.rb with ruby-2.0

git-svn-id: https://svn.code.sf.net/p/rubycocoa/svn/trunk/src@2461 f4f36d40-9719-0410-9868-dde021a23eda
Fix error of standaloneify.rb with rubygems-2.1.10

standaloneify.rb with rubygems-2.1.10 fails with the following error:

    `method_missing': undefined method `installation_path' for
    #<Gem::Specification:...> (NoMethodError)

git-svn-id: https://svn.code.sf.net/p/rubycocoa/svn/trunk/src@2462 f4f36d40-9719-0410-9868-dde021a23eda