Creates a layouts/ folder for keymaps shared between keyboards (#1609)

* include variables and .h files as pp directives

* start layout compilation

* split ergodoxes up

* don't compile all layouts for everything

* might seg fault

* reset layouts variable

* actually reset layouts

* include rules.mk instead

* remove includes from rules.mk

* update variable setting

* load visualizer from path

* adds some more examples

* adds more layouts

* more boards added

* more boards added

* adds documentation for layouts

* use lowercase names for LAYOUT_

* add layout.json files for each layout

* add community folder, default keymaps for layouts

* touch-up default layouts

* touch-up layouts, some keyboard rules.mk

* update documentation for layouts

* fix up serial/i2c switches

layouts/community/ergodox/german-lukas/README.md

@@ -0,0 +1,12 @@
+# About this keymap
+
+This keymap is based on the qwertz layout.
+It has a key for pressing the left control and the left alt key at once.
+
+Linux makes a difference between AltGr and Control + Alt. Some keybindings are easier to press now.
+
+Also, I added a layer for pressing Control + Alt + F-Keys very fast.
+
+# Layer
+
+Each layer in the *keymap.c*-file has a comment showing the mappings of the layer.