Add description of rb_any_to_s()
Add `。`
Merge pull request #152 from yui-knk/fix/spec

Add `。`
Merge pull request #151 from takiy33/rb_any_to_s

Add description of rb_any_to_s()
Fix Japanese.
Remove deleted function in 1.9.1
Update object.c functions.
Add UncaughtThrowError since 2.2.0
Add String#unicode_normalize, #unicode_normalize! and #unicode_normalized? since 2.2.0