refactor(index.html): non-redundant data access

Previously we would define information about the program types
in two places, once for the index, and once per program type.
Now within the index.html, we just load the respective program type
information to have access to the latest at all times.

Closes #104
[skip ci]

etc/api/shared.yaml

@@ -15,12 +15,8 @@ api:
 make:
   # All known program ids.
   types:
-    - id: api
-      target_suffix: ''
-      documentation_engine: rustdoc
-    - id: cli
-      target_suffix: -cli
-      documentation_engine: mkdocs
+    - api
+    - cli
 directories:
   # directory under which all generated sources should reside
   output: gen