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This modification is required in order to bypass the plugin unloading
mechanism in the ROOT plugin manager. The new regexes are functionally
equivalent with the original ones, but aren't completely the same.

This functionality is required in order to preserve backwards
compatibility with TAlien and how legacy code handles return
and error values.

This modification in CMakeLists is introduced to avoid problems
with building this project with OpenSSL compiled by alibuild.
Without these modifications the build fails because JAlien-ROOT
includes libwebsockets headers which further include the OpenSSL
headers. The OpenSSL headers may not be reachable if they are not
available in the system include path, for example in alibuild
workspace.

We don't check for the library to be under `$ROOTSYS` before loading any longer,
as this is no longer the case

* Very simple CMake file relying on ROOT's CMake
* `Find` modules for JSON-C and libwebsockets

No need to keep ROOT's structure, since we won't need to sync it to ROOT anymore