Update devguide.md
Update devguide.md

Formatting, grammar.
mmnelemane/crowbar,rhafer/crowbar,tserong/crowbar,aplanas/crowbar,crowbar/crowbar,rhafer/crowbar,dirkmueller/crowbar,aspiers/crowbar,rhafer/crowbar,SUSE-Cloud/crowbar,MaximilianMeister/crowbar,MaximilianMeister/crowbar,aspiers/crowbar,crowbar/crowbar,aplanas/crowbar,SUSE-Cloud/crowbar,toabctl/crowbar,rsalevsky/crowbar,tserong/crowbar,vwallfahrer/crowbar,vwallfahrer/crowbar,nkrinner/crowbar,toabctl/crowbar,rsalevsky/crowbar,dirkmueller/crowbar,nkrinner/crowbar,mmnelemane/crowbar