Separate firmware design out of user-guide.md

Move the firmware design documentation out of user-guide.md and into a new file - firmware-design.md. Reformat the section headers. Change-Id: I664815dd47011c7c1cf2202aa4472a8fd78ebb92

Separate firmware design out of user-guide.md
Move the firmware design documentation out of user-guide.md and into a new file - firmware-design.md. Reformat the section headers. Change-Id: I664815dd47011c7c1cf2202aa4472a8fd78ebb92
247f60bc · Dan Handley · 3505c044 · 247f60bc · 247f60bc
Commit 247f60bc authored Feb 25, 2014 by Dan Handley
--- a/docs/firmware-design.md
+++ b/docs/firmware-design.md
--- a/docs/user-guide.md
+++ b/docs/user-guide.md