Update README and CMake with the BBP closure (#1566)

CMakeLists.txt

@@ -367,3 +367,11 @@ message(STATUS "--------------------+-------------------------------------------
 message(STATUS " See documentation : https://github.com/BlueBrain/nmodl/")
 message(STATUS "--------------------+--------------------------------------------------------")
 message(STATUS "")
+
+message(
+  WARNING
+    "=========================================================
+This repository is unmaintained. NMODL is now developed
+as part of:
+  https://github.com/neuronsimulator/nrn
+==========================================================")

README.md

@@ -0,0 +1,22 @@
+# The NMODL Framework
+
+> [!WARNING]
+>
+> NMODL has been fully integrated into the NEURON repository. There will
+> be no further development efforts NMODL as an independent project.
+>
+> All future development will happen at:
+>  https://github.com/neuronsimulator/nrn
+
+## Funding & Acknowledgment
+
+The development of this software was supported by funding to the Blue
+Brain Project, a research center of the École polytechnique fédérale de
+Lausanne (EPFL), from the Swiss government’s ETH Board of the Swiss
+Federal Institutes of Technology. In addition, the development was
+supported by funding from the National Institutes of Health (NIH) under
+the Grant Number R01NS11613 (Yale University) and the European Union’s
+Horizon 2020 Framework Programme for Research and Innovation under the
+Specific Grant Agreement No. 785907 (Human Brain Project SGA2).
+
+Copyright © 2017-2024 Blue Brain Project, EPFL