Keymap: Redox / jeherve: updates (#4694)

* Start using send_unicode_hex_string for shrug

See https://docs.qmk.fm/#/feature_unicode?id=send_unicode_hex_string

* Make sure one can come back to main layer after tapping to NAV

* Add 4 new keys to symbol layer

~, `, =, +, are now more accesssible. No need to reach out far from home row anymore

* Add two new macro keys

I did not have much use for the Expose key and the right Command key, so opted to replace those with 2 Macros:

- One to invoke Alfred: https://www.alfredapp.com/ => Opt + Space
- One to invoke 1password: https://1password.com/ => Cmd + Opt + \

* Update readme to mention changes in new version

* Remove unneeded short definition

* Shorter name for our custom key

See https://github.com/qmk/qmk_firmware/pull/4694#discussion_r243341864

* Make macros one-liners

See https://github.com/qmk/qmk_firmware/pull/4694#discussion_r243341487

* Switch to using eeconfig_init_user to set Unicode mode

See https://github.com/qmk/qmk_firmware/pull/4694#issuecomment-449151724

keyboards/redox/keymaps/jeherve/readme.md

@@ -1,7 +1,7 @@
 # A Colemak keymap for the Redox keyboard
 
 ----
-![jeherve-redox-layout-3](https://user-images.githubusercontent.com/426388/45171716-69888200-b203-11e8-822d-7bc91f9f6c07.jpg)
+![jeherve-redox-layout-4](https://user-images.githubusercontent.com/426388/50276398-2664be80-0442-11e9-86b9-fbd0f4275354.png)
 
 ----
 
@@ -25,6 +25,11 @@ My keymap uses 5 layers:
 
 ## Changelog
 
+- 2018.12.20
+	- 2 new Macro keys, to invoke [Alfred](https://www.alfredapp.com/) and [1Password](https://1password.com/).
+	- No more Right Command key or Expose key, I didn't use those much.
+	- Updates to use newer QMK function to call ¯\_(ツ)_/¯
+	- Fix: you can now move back to the base layer when double tapping the thumb keys to switch to the Nav layer. 👍
 - 2018.09.06
 	- Initial submission to QMK. It's alive! ⌨️