[core] restructure to allow PIP packaging

OK - so I have to admit I *hate* the fact that PIP seems to require a
subdirectory named like the library.

But since the PIP package is something really nifty to have (thanks to
@tony again!!!), I updated the codebase to hopefully conform with what
PIP expects. Testruns so far look promising...

bumblebee_status/modules/contrib/layout.py

@@ -0,0 +1,78 @@
+# pylint: disable=C0111,R0903
+
+"""Displays and changes the current keyboard layout
+
+Requires the following executable:
+    * setxkbmap
+
+contributed by `Pseudonick47 <https://github.com/Pseudonick47>`_ - many thanks!
+"""
+
+import core.module
+import core.widget
+import core.input
+
+import util.cli
+
+
+class Module(core.module.Module):
+    def __init__(self, config, theme):
+        super().__init__(config, theme, core.widget.Widget(self.current_layout))
+
+        core.input.register(self, button=core.input.LEFT_MOUSE, cmd=self.__next_keymap)
+        core.input.register(self, button=core.input.RIGHT_MOUSE, cmd=self.__prev_keymap)
+
+    def __next_keymap(self, event):
+        self._set_keymap(1)
+
+    def __prev_keymap(self, event):
+        self._set_keymap(-1)
+
+    def _set_keymap(self, rotation):
+        layouts = self.get_layouts()
+        if len(layouts) == 1:
+            return  # nothing to do
+        layouts = layouts[rotation:] + layouts[:rotation]
+
+        layout_list = []
+        variant_list = []
+        for l in layouts:
+            tmp = l.split(":")
+            layout_list.append(tmp[0])
+            variant_list.append(tmp[1] if len(tmp) > 1 else "")
+
+        util.cli.execute(
+            "setxkbmap -layout {} -variant {}".format(
+                ",".join(layout_list), ",".join(variant_list)
+            ),
+            ignore_errors=True,
+        )
+
+    def get_layouts(self):
+        try:
+            res = util.cli.execute("setxkbmap -query")
+        except RuntimeError:
+            return ["n/a"]
+        layouts = []
+        variants = []
+        for line in res.split("\n"):
+            if not line:
+                continue
+            if "layout" in line:
+                layouts = line.split(":")[1].strip().split(",")
+            if "variant" in line:
+                variants = line.split(":")[1].strip().split(",")
+
+        result = []
+        for idx, layout in enumerate(layouts):
+            if len(variants) > idx and variants[idx]:
+                layout = "{}:{}".format(layout, variants[idx])
+            result.append(layout)
+        return result if len(result) > 0 else ["n/a"]
+
+    def current_layout(self, widget):
+        layouts = self.get_layouts()
+        return layouts[0]
+
+
+# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4