(RubyForge#15447)

* math.c: fix typo.
-- 

M    ChangeLog
M    math.c
M    ext/json/ext/generator/generator.c
M    ext/json/ext/parser/parser.rl
M    ext/json/ext/parser/parser.c
M    lib/json/version.rb
M    lib/json/editor.rb
M    lib/json/common.rb
M    lib/json/pure/parser.rb
M    test/json/test_json_unicode.rb
M    test/json/test_json_fixtures.rb
M    test/json/test_json_generate.rb
M    test/json/test_json_addition.rb
M    test/json/test_json.rb
M    test/json/runner.rb


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@14044 b2dd03c8-39d4-4d8f-98ff-823fe69b080e