With these changes, we no longer need to manually find the LIEF library
by filename. CMake takes care of generating the LIEF::LIEF target and
library location for us in the exported target set. This is basically a
requirement when using external dependencies because the original
functionality did not take care of this.
I have updated the example projects to make sure that they will work
with this new setup. In doing so, I changed quite a bit to more closely
follow CMake best practices that I hope we can agree on to both improve
reliability and reduce maintenance and support questions for people who
configure LIEF with external dependencies.
This project still supports finding static or shared LIEF libraries in
the same install prefix using the find_package COMPONENTS method.
This project still supports development of other projects that want to
use LIEF without installing. Just specify the following option during
configuration of your project that depends on LIEF:
```cmake
cmake -DLIEF_DIR=<LIEF_BUILD_DIR> ...
```
Romain Thomas