Add subtitle to docs and fix primitive type links (#6724)

Signed-off-by: Nick Cameron <nrc@ncameron.org>

docs/kcl-std/functions/std-units-toMeters.md

@@ -1,17 +1,18 @@
 ---
-title: "std::units::toMeters"
+title: "units::toMeters"
+subtitle: "Function in units"
 excerpt: "Convert a number to meters from its current units."
 layout: manual
 ---
 
 Convert a number to meters from its current units.
 
-
-
 ```kcl
 units::toMeters(@num: number(m)): number(m)
 ```
 
+
+
 ### Arguments
 
 | Name | Type | Description | Required |