* numeric.c (rb_enc_uint_char): raise RangeError when added codepoint
	  is invalid. [Feature #5855] [Bug #5863] [Bug #5864]

	* string.c (rb_str_concat): ditto.

	* string.c (rb_str_concat): set encoding as ASCII-8BIT when the string
	  is US-ASCII and the argument is an integer greater than 127.

	* regenc.c (onigenc_mb2_code_to_mbclen): rearrange error code.

	* enc/euc_jp.c (code_to_mbclen): ditto.

	* enc/shift_jis.c (code_to_mbclen): ditto.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_3@34501 b2dd03c8-39d4-4d8f-98ff-823fe69b080e