Pull out sendstring variations to their own files.

Instead of having all sendstring keycode mappings in the main quantum.c
file, give each one its own file in keymap_extras that can be #included
in a user's keymap. If one is included, it will define the appropriate
lookup tables and overwrite the weak definitions in quantum.c.
(Including more than one sendstring definition will fail at compile
time.)

Update @rai-suta's test keymap to match, as well as the documentation.

1 files changed, 7 insertions, 1 deletions

diff --git a/docs/macros.md b/docs/macros.md
index 1418d24ab..bbf51434a 100644
--- a/docs/macros.md
+++ b/docs/macros.md
@@ -41,7 +41,7 @@ A macro can include the following commands:
 
 ## Sending strings
 
-Sometimes you just want a key to type out words or phrases. For the most common situations we've provided `SEND_STRING()`, which will type out your string for you instead of having to build a `MACRO()`. Right now it assumes a US keymap with a QWERTY layout, so if you are using something else it may not behave as you expect.
+Sometimes you just want a key to type out words or phrases. For the most common situations we've provided `SEND_STRING()`, which will type out your string for you instead of having to build a `MACRO()`.
 
 For example:
 
@@ -58,6 +58,12 @@ const macro_t *action_get_macro(keyrecord_t *record, uint8_t id, uint8_t opt) {
 };
 ```
 
+By default, it assumes a US keymap with a QWERTY layout; if you want to change that (e.g. if your OS uses software Colemak), include this somewhere in your keymap:
+
+```
+#include <sendstring_colemak.h>
+```
+
 ## Mapping a Macro to a key
 
 Use the `M()` function within your `KEYMAP()` to call a macro. For example, here is the keymap for a 2-key keyboard: