Move copy_headers.sh and formath.sh from root.
Debian: use default build dir (obj-x86_64-linux-gnu)
Debian: add test after build (GLIBC_required_version)
cmake: dont run copy headers if already copied
* Fix includes
* Faster compile
* WTFix
* Limit compile and linking jobs according to available memory
* Add comment
* fix
* Remove ALL from copy-headers target
* Freebsd fix
* Better
* cmake: split use libcxx