This diff adds new install targets:

• An install-all target which install everything including the

EXCLUDE_FROM_ALL components.

• The man pages are now part of a dedicated component which can be

installed via install-manpages.

• Each component has its own dedicated installation target

install-<component>.

Depends on D7224.

mkdir -p install
cmake -GNinja .. -DCMAKE_INSTALL_PREFIX=install

Try a few install targets and check the expected files are installed:

ninja install-bitcoin-bench
ninja install-bitcoind
ninja install-manpages
ninja install-all

Check there is no behavior change:

ninja install