Update README.md

Render line breaks for shell commands.
Add crunch to travis list
Add an explicit `make depend` step for mirage 1.2.0
Merge pull request #43 from Chris00/patch-1

Update README.md (line breaks)
Merge pull request #44 from avsm/master

Fixes for DNS 0.9.1 and make depend
Merge branch 'master' of github.com:mirage/mirage-skeleton

Conflicts:
	Makefile