Keep snippet vars definitions in a single format across all snippets and documentation.

The format is:

# var-name: value

Previously snippets used a mixture of the following formatting:

#var-name: value
#var-name : value
# var-name: value
# var-name : value

snippets/c++-mode/beginend

@@ -1,4 +1,4 @@
-#name : v.begin(), v.end()
+# name: v.begin(), v.end()
 # key: beginend
 # --
 ${1:v}.begin(), $1.end

snippets/c++-mode/class

@@ -1,4 +1,4 @@
-#name : class ... { ... }
+# name: class ... { ... }
 # key: class
 # --
 class ${1:Name}

snippets/c++-mode/ns

@@ -1,4 +1,4 @@
-#name : namespace ...
+# name: namespace ...
 # key: ns
 # --
 namespace 

snippets/c++-mode/template

@@ -1,4 +1,4 @@
-#name : template <typename ...>
+# name: template <typename ...>
 # key: template
 # --
 template <typename ${T}>

snippets/c++-mode/using

@@ -1,4 +1,4 @@
-#name : using namespace ... 
+# name: using namespace ... 
 # key: using
 # --
 using namespace ${std};