Create sv_SE Qwerty layout for ErgoDox

*NOTE:* it might still be desirable to set the software layout to sv_SE in your
OS.

Swedish (sv_SE) Qwerty layout for ErgoDox, based on the Default configuration

I have tried making this as close of a match I could between the [default
ErgoDox EZ configuration](https://ergodox-ez.com/pages/our-firmware) and a
standard Swedish Qwerty layout.

Notable differences from default:
=================================

* There are three special character buttons (acute accent, circumflex/tilde and
  apostrophe/asterisk) that don't have any buttons to map to naturally. I've put
  these at other places:

    * Acute accent (´) can be found in the lower left corner, conveniently
      placed to reach for making an é.

    * Apostrophe (') was put in the lower left corner, close to acute accent.

    * Circumflex (^) and asterisk (*) was placed in the lower right corner.

    * Tilde (~) and diaeresis (¨) I couldn't find a good place for, so I left
      those out. I could only get the buttons to produce a single one of the
      characters. How can I get it to work properly?

* The Alt button on right thumb was exchanged for AltGr (RAlt).

* I changed the backslash in the numpad (layer 1) for a minus. Thought it was
  more sensible.

* I didn't find a good place for the "<>|" button, so that one was left out.
  That is a problem that really needs to be resolved. Pipe can be found on layer
  one, however.

1 files changed, 52 insertions, 0 deletions

diff --git a/quantum/keymap_extras/keymap_swedish.h b/quantum/keymap_extras/keymap_swedish.h
new file mode 100644
index 0000000000..dcfad720d0
--- /dev/null
+++ b/quantum/keymap_extras/keymap_swedish.h
@@ -0,0 +1,52 @@
+/* Copyright 2017 Andreas Lindhé
+ *
+ * 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 KEYMAP_SWEDISH_H
+#define KEYMAP_SWEDISH_H
+
+#include "keymap_nordic.h"
+
+// There are slight differrences in the keyboards in the nordic contries
+
+// Swedish redifinitions from the nordic keyset
+#undef  NO_AE
+#define NO_AE   KC_QUOT  // ä
+#undef  NO_CIRC
+#define NO_CIRC LSFT(KC_RBRC)  // ^
+#undef  NO_GRV
+#define NO_GRV  LSFT(NO_BSLS)  //
+#undef  NO_OSLH
+#define NO_OSLH KC_SCLN  // ö
+
+// Additional Swedish keys not defined in the nordic keyset
+#define NO_AA   KC_LBRC  // å
+#define NO_ASTR LSFT(KC_BSLS)  // *
+
+// Norwegian unique MAC characters (not vetted for Swedish)
+#define NO_ACUT_MAC KC_EQL  // =
+#define NO_APOS_MAC KC_NUBS  // '
+#define NO_AT_MAC   KC_BSLS  // @
+#define NO_BSLS_MAC ALGR(LSFT(KC_7)) // '\'
+#define NO_DLR_MAC  LSFT(KC_4) // $
+#define NO_GRV_MAC ALGR(NO_BSLS) // `
+#define NO_GRTR_MAC LSFT(KC_GRV)  // >
+#define NO_LCBR_MAC ALGR(LSFT(KC_8))  // }
+#define NO_LESS_MAC KC_GRV  // >
+#define NO_PIPE_MAC ALGR(KC_7)  // |
+#define NO_RCBR_MAC ALGR(LSFT(KC_9))  // }
+
+#endif
+