Updates to noroadsleft keymap for KC60 (#5127)

* NUBS_Z: initial version

Create a keycode that is normally Z, but KC_NUBS when tapped while Alt is being held.

This removes the possibility of using an Alt+Z shortcut.

* NUBS_Z: modification

Modify NUBS_Z macro to only use alternate operation if Right Alt is being held, rather than responding to either Alt key.

Also add QMK version keycode to System layer, Equals key.

* Remove unneeded breaks from process_record_user

* Macro refactoring

- removed G_RST and G_C10R macros
- updated G_BRCH macro
  - outputs `master` if used while Shift is held down; or my git alias for the current branch otherwise
- updated G_FTCH macro
  - outputs `git pull upstream ` if used with Shift; `git fetch upstream ` otherwise
- swapped `modifiers` variable for `get_mods()` function directly for checking modifier state
- swapped keymap-level modifier mask macros for QMK-core mod mask macros (thanks vomindoraan #4337)
- renamed MODS_RALT_MASK to MOD_MASK_RALT (more consistent with the above change)

* Update readme files

keyboards/kc60/keymaps/noroadsleft/readme_ch4.md

@@ -7,8 +7,6 @@
   4. **Function Layers**
   5. [Other Layers](./readme_ch5.md)
 
-### Last updated: September 2, 2018, 1:03 PM UTC-0700
-
 
 ----
 
@@ -44,7 +42,7 @@ Based on the Windows function layer, but removes some functions that are pointle
 
 Keycode(s) Sent                   | Notes
 :-------------------------------- | :----
-[`Q2_GRV`](./keymap.c#L208-L216)  | Sends `KC_GRV`, then enables the Dvorak, Quake 2 Dvorak, and Quake 2 Console layers.
+[`Q2_GRV`](./keymap.c#L194-L201)  | Sends `KC_GRV`, then enables the Dvorak, Quake 2 Dvorak, and Quake 2 Console layers.