added functions utfnlen() and utfnshift()
implemented String_ctor(type conversion) and Str_valueOf, added some empty methods
correct functions Str_fromCharCode(), _charAt(), Str_charAt(), Str_charCodeAt(), Str_concat(), Str_indexOf(), Str_lastIndexOf(), Str_localeCompare(), Str_match(), Str_replace(), Str_search(), Str_slice(), Str_split()
correct functions: Str_substr(), Str_toLowerCase(), Str_toLocaleLowerCase(), Str_toUpperCase(), Str_toLocaleUpperCase(), Str_trim()
added function re_nextexc()
rename re_nextexc() to nextesc()
push_string_literal() corrected
get_tok() corrected to support number literals like ".\d"
v7_stringify() corrected for negative integer numbers
v7_strdup() and v7_init_str() corrected
cosmetic
check_str_re_conv() moved from string.c to util.c
function _conv_to_num() added
corrected type conversion in arith()
corrected type conversion in parse_unary(), logical_op(), parse_bitwise_and(), parse_bitwise_xor(), parse_bitwise_or(). Added algorithm for TOK_TILDA.
_conv_to_int() added
added type conversion in Str_fromCharCode(), _charAt(), Str_indexOf(), Str_lastIndexOf(), Str_slice(), Str_substr()
_charAt() without argument corrected
String_ctor() corrected
correct esc chars in regexp