regexp search&replace uses char (3 problems)

[roj234]

problem 1: not support chinese regexp replace, "[尬]" matches "哈", and rarely match partial character (2/3 of UTF-8) problem 2: enabled regexp replace, and select multi lines, and input Ctrl+H (see picture) problem 3: regexp cannot use \r or \n

[zufuliu]

problem 2: enabled regexp replace, and select multi lines, and input Ctrl+H (see picture)

Fixed by ea3e54fe05f6fe2779bb30f3caf7d8fba249436d, the reset should be fixed after change regex engine to Boost (#725).