add -color to build -h command

command/build.go

@@ -279,10 +279,11 @@ Usage: packer build [options] TEMPLATE
 
 Options:
 
+  -color=false               Disable color output (on by default)
   -debug                     Debug mode enabled for builds
+  -except=foo,bar,baz        Build all builds other than these
   -force                     Force a build to continue if artifacts exist, deletes existing artifacts
   -machine-readable          Machine-readable output
-  -except=foo,bar,baz        Build all builds other than these
   -only=foo,bar,baz          Only build the given builds by name
   -parallel=false            Disable parallelization (on by default)
   -var 'key=value'           Variable for templates, can be used multiple times.