Add keyboard shortcuts documentation (#62)

* Add keyboard shortcuts documentation

* rearrange Keyboard Shortcuts section to higher level

Author: Ziesie1

docs/en/user-guide/shortcuts.md

@@ -0,0 +1,7 @@
+# Using Keyboard Shortcuts
+
+Keyboard shortcuts allow you to navigate quickly through Gramps Web without using your mouse, saving you clicks and time. 
+
+From any view, you can jump directly to common actions and pages with just a few keystrokes. For example, press **`s`** on your keyboard to open the search, **`g`** + **`c`** to navigate to the Family Tree, or **`n`** + **`p`** to create a new person. 
+
+To see a complete list of all available keyboard shortcuts, simply press **`?`** at any time.

mkdocs.yml

@@ -49,6 +49,7 @@ nav:
           - DNA matches: user-guide/dna-matches.md
           - Chromosome browser: user-guide/chromosome-browser.md
           - Y-DNA: user-guide/y-dna.md
+      - Keyboard Shortcuts:  user-guide/shortcuts.md
       - Revision history: user-guide/revisions.md
       - Advanced features:
           # - DNA:  user-guide/dna.md