basic_regex constructor inconsistencies

[sdutoit]

From an email to cxxeditor:

In the Working Draft #3337 of the C++ Standard in section
28.8 Class template basic_regex

there is written

explicit basic_regex(const charT* p, flag_type f = regex_constants::ECMAScript);

Take into account the keyword explicit.

However in the description of this constructor this keyword is abset

basic_regex(const charT* p, flag_type f = regex_constants::ECMAScript);

The simialar defect was pointed out by Daniel Krügler for the constructor

template <class ST, class SA>
explicit basic_regex(const basic_string<charT, ST, SA>& p,
flag_type f = regex_constants::ECMAScript);

In its description the keyword explicit is also abset.

template <class ST, class SA>
basic_regex(const basic_string<charT, ST, SA>& s,
flag_type f = regex_constants::ECMAScript);