docs(style-guide): a few fixes (#3534)

Author: Foxandxss

public/docs/ts/latest/guide/style-guide.jade

@@ -1371,9 +1371,9 @@ a(href="#toc") Back to top
     **Consider** using the name SharedModule when the contents of a shared 
     module are referenced across the entire application.
 
-.s-rule.do
+.s-rule.avoid
   :marked
-    **Do** not provide services in shared modules. Services are usually 
+    **Avoid** providing services in shared modules. Services are usually 
     singletons that are provided once for the entire application or 
     in a particular feature module.
 
@@ -1785,7 +1785,7 @@ a(href="#toc") Back to top
     **Do** use the `@Input()` and `@Output()` class decorators instead of the `inputs` and `outputs` properties of the 
     `@Directive` and `@Component` metadata:
 
-.s-rule.do
+.s-rule.consider
   :marked
     **Consider** placing `@Input()` or `@Output()` on the same line as the property it decorates.