actuation point adjustment for fc980c and fc660c (#2134)

* add i2c lib submodule

* add actuation point adjustment to fc980c

* add actuation point adjustment to fc660c also.

* use https for i2c submodule

* move to existing i2c lib

* properly remove old submodule

* oops, forgot some files for the fc660c

keyboards/fc660c/actuation_point.h

@@ -0,0 +1,32 @@
+/*
+Copyright 2017 Balz Guenat
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef ACTUATION_POINT_H
+#define ACTUATION_POINT_H
+
+#include <stdint.h>
+
+// see keymaps/actuation-point-example to see how these functions can be used.
+uint8_t read_rdac(void);
+uint8_t read_eeprom(void);
+void actuation_point_up(void);
+void actuation_point_down(void);
+
+// be careful with this.
+void adjust_actuation_point(int offset);
+
+#endif