cmd/bosun: upgrade docker image to go1.4
cmd/bosun: enforce crit and warn have same return types
cmd/bosun: add alert() function to execute an alert's expression
gofmt
cmd/bosun: golint cleanup for capitalization
cmd/bosun: golint cleanup for comments
cmd/bosun: golint cleanup for receiver arg name
cmd/scollector: golint Id -> ID
cmd/bosun: golint cleanup