Makefile: bump version to 2.7.0
Makefile: bump version to 2.7.0

StoneDot/lrexlib,LuaDist/lrexlib-pcre,LuaDist/lrexlib-oniguruma,LuaDist/lrexlib-posix,LuaDist/lrexlib-posix,StoneDot/lrexlib,LuaDist/lrexlib-gnu,LuaDist/lrexlib-tre,LuaDist/lrexlib-gnu,LuaDist/lrexlib-oniguruma,LuaDist/lrexlib-tre,LuaDist/lrexlib-pcre