source/tools.html: White space

I've killed for less!

Signed-off-by: Alan Orth <alan.orth@gmail.com>
source/what-is-linux.html: Remove quote from Dennis Ritchie

Signed-off-by: Alan Orth <alan.orth@gmail.com>
source/tools.html: Re-work tools section for Dennis Ritchie intro

Signed-off-by: Alan Orth <alan.orth@gmail.com>
source/tools.html: Re-work tools section

Give better examples of tools and workflows which are relevant to
us.

Signed-off-by: Alan Orth <alan.orth@gmail.com>
Add notes / example about reveal.js

Signed-off-by: Alan Orth <alan.orth@gmail.com>
source/tools.html: Add note about collaboration

Signed-off-by: Alan Orth <alan.orth@gmail.com>
Move sections about Linux spirit to "dog food" slide

Signed-off-by: Alan Orth <alan.orth@gmail.com>