Fix clang compilation issue (#634)
Resolve deprecation warnings of gcc 9 (#633)
Merge #638
Factor out recursion from weighted matching algorithms (#638)
Merge #640
Implement CplLp::write() for LP format (#640)
Bugfixes in CplexBase and ClpLp (#639)
Update CMakeLists.txt to match current CMAKE versions (#641)
Backport relevant part of bugfix [4add05447ca0] to branch 1.3 (#623)
Backport relevant parts of bugfixes [ad22262328b3], [61fdd06833a6] and [4add05447ca0] to branch 1.2 (#623)