Merge branch 'develop'
Merge branch 'develop'
Merge branch 'develop'
Merge branch 'develop'
Merge branch 'develop'
Initialize m_position, m_end, and m_flags

The constructor for basic_regex_formatter left m_position, m_end, and m_flags uninitialized, as uncovered by Coverity CID12310. We now value-initialize them in the initializer list.
Merge branch 'patch-3' of https://github.com/tempoz/regex into develop
Silence Covertity warnings, see https://github.com/boostorg/regex/pull/7
Initialize all members in initializer list, see https://github.com/boostorg/regex/pull/6