GPS refactor & license text updates (#601)

- Split up `gps-generic-module` into:
  - `gps-generic-module` that contains only interfaces/configs/bindings (Apache license)
  - `gps-meshtastic-module` that contains an implementation (GPL license)
- Update `LICENSE.md` for changes, but also added clarifications
- Added licenses to directories where they were missing
- Changed license of some test projects from GPL to Apache.

Drivers/gps-meshtastic-module/source/module.cpp

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-3.0
+#include <tactility/driver.h>
+#include <tactility/module.h>
+
+extern "C" {
+
+extern Driver meshtastic_gps_driver;
+
+static Driver* const meshtastic_generic_drivers[] = {
+    &meshtastic_gps_driver,
+    nullptr
+};
+
+Module gps_generic_module = {
+    .name = "gps-meshtastic",
+    .drivers = meshtastic_generic_drivers
+};
+
+}