v2.7

• Make vector resize take a second argument for fill value.
• vector dtor should not call dtors when linked.
• exchange algo should be c++14 only.
• Add required explicit scoping for swap in pair and smart pointers.
• Make swap implementation shared with c++98.
• Fix some warnings from -Weffc++.
• Fix new warnings and errors from gcc 8.1.
• Add workaround for gcc 8.1 bug 85695.
• ifdef out _long4grain alignof spec on 32bit platforms.
• Replace C-style casts with C++-style casts.
• Remove obsolete --without-mmx configure flag.

v2.6

• Fix erase cow sometimes truncating strings.
• Fix hang in istringstream read_number at end of stream.
• Fix test failures new with gcc 7.2.
• Fix configure directory detection with new gcc.
• Remove operator<< and operator>> templates for ustl types.
• Add pkg-config file
• Do not use memcpy in fallback implementation of copy_n_fast.
• Remove -march=native from default compiler flags.
• Add configure --with-native flag.