Updated How tos (markdown)

How-To's.md

@@ -4,18 +4,22 @@ This page contains some usage information for common tasks when using Todo.txt C
 
 You can exclude words, contexts and projects from a `todo list` using the `-` operator, for example, to find things you need to send, except those by email:
 
-    todo ls "send -email"
-    14 Send Father's day card
-    11 Send keys back @postoffice
-    --
-    TODO: 2 of 19 tasks shown
+```bash
+$ todo ls "send -email"
+14 Send Father's day card
+11 Send keys back @postoffice
+--
+TODO: 2 of 19 tasks shown
+```
 
 This can also be used on projects and operators:
 
-    todo ls "download update -@home"
-    02 Download the new vm software @work
-    09 Update Twitter app @phone
-    --
-    TODO: 2 of 19 tasks shown
+```bash
+$ todo ls "download update -@home"
+02 Download the new vm software @work
+09 Update Twitter app @phone
+--
+TODO: 2 of 19 tasks shown
+```
 
 Note that while on search engines `+` will force a term to be included, this is a simple search tool and `+`s are used for projects.