Generate API docs from source code comments (#2491)

* Generate api docs from source code

* Add a bunch of doxygen comments

* more doxygen comments

* Add the in-progress api docs

* script to generate docs from travis

* Add doc generation to the travis job

* make travis_docs.sh commit the work it does

* make sure the docs script exits cleanly

tmk_core/common/magic.c

@@ -14,6 +14,10 @@
 
 keymap_config_t keymap_config;
 
+/** \brief Magic
+ *
+ * FIXME: Needs doc
+ */
 void magic(void)
 {
     /* check signature */