Added more documentation

src/services/hypermedia.ml

-(* The base URL for fetching all data  *)
-let baseUrl = "http://localhost:6543";;
-
-(* Headers when fetching schema information  *)
-let headersForSchema = [|
-  ("Content-Type", "application/schema+json");
-  ("Accept", "application/schema+json")
-|];;
-
-(* Headers when fetching data  *)
-let headersForResources = [|
-  ("Content-Type", "application/json");
-  ("Accept", "application/json")
-|];;
-
 type reference = { ref: string }
 
 type schemaLink = {
@@ -66,6 +51,7 @@ and entityValue =
   | ValueObject of entity
 
 
+(* Module for entity manipulation *)
 module Entity = struct
   let get entity key = begin
     (List.find (fun p -> p.name = key) entity.properties).value
@@ -83,6 +69,7 @@ module Entity = struct
 end
 
 
+(* Module for decoding a JSON response into OCaml *)
 module Decode = struct
   exception DecodeError of string
 
@@ -185,7 +172,9 @@ module Decode = struct
 end
 
 
+(* Utility module *)
 module Utils = struct
+  (* Renders a template string using the specified entity *)
   let produce template entity = begin
     let re = [%re "/\{([a-zA-Z_][a-zA-Z0-9_]*)\}/g"] in
     let break = ref false in
@@ -218,13 +207,31 @@ module Utils = struct
 end
 
 
+(* Module for fetching data *)
 module Fetch = struct
+  (* The base URL for fetching all data *)
+  let baseUrl = "http://localhost:6543";;
+
+  (* Headers when fetching schema information *)
+  let headersForSchema = [|
+    ("Content-Type", "application/schema+json");
+    ("Accept", "application/schema+json")
+  |];;
+
+  (* Headers when fetching data *)
+  let headersForResources = [|
+    ("Content-Type", "application/json");
+    ("Accept", "application/json")
+  |];;
+
+  (* Take a path as a list of segments and convert it to a string *)
   let rec getTarget path =
     match path with
     | [] -> ""
     | [first] -> "/" ^ first
     | first :: others -> "/" ^ first ^ (getTarget others)
 
+  (* Get a promise for fetching a schema for the specified target path *)
   let do_fetch_schema path =
     let headers = Fetch.HeadersInit.makeWithArray headersForSchema in
     let reqInit = () |> Fetch.RequestInit.make ~headers: headers in
@@ -237,6 +244,7 @@ module Fetch = struct
       |> catch (fun _err -> resolve None)
     )
 
+  (* Get a promise for fetching data at the specified target path *)
   let do_fetch_data path =
     let headers = Fetch.HeadersInit.makeWithArray headersForResources in
     let reqInit = () |> Fetch.RequestInit.make ~headers: headers in
@@ -249,6 +257,7 @@ module Fetch = struct
       |> catch (fun _err -> resolve None)
     )
 
+  (* Executes a fetch operation f for a path and react to failure or success *)
   let fetch f path on_fail on_success =
     let promise = f path in
     Js.Promise.(
@@ -261,9 +270,11 @@ module Fetch = struct
       |> ignore
     )
 
+  (* Fetch the schema for a resource at the path and react to failure or success *)
   let fetch_shema path on_fail on_success =
     fetch do_fetch_schema path on_fail on_success
 
+  (* Fetch the data for a resource at the path and react to failure or success *)
   let fetch_data path on_fail on_success =
     fetch do_fetch_data path on_fail on_success
 end
\ No newline at end of file