Update docs

lib/cloud_vision.ex

@@ -4,6 +4,15 @@ defmodule CloudVision do
    image_properties: "IMAGE_PROPERTIES", unspecified: "TYPE_UNSPECIFIED"
  ]
 
+  @doc """
+  Args:
+    * `img_path` - relative path to the image file from local directory or root of google cloud storage
+    * `options` - Keyword list of options
+
+  Options:
+    * `:from` - where to find the file. It can be `:storage` or `:local`. Default is `:local`
+    * `:features` - list of detection features you want to use (`@features`)
+  """
   def analyze(img_path, opts \\ []) do
     case CloudVision.Client.post("/images:annotate", build_params(img_path, opts) |> Poison.encode!) do
       {:ok, %HTTPoison.Response{status_code: x, body: body}} when x in 200..299 ->
@@ -24,7 +33,6 @@ defmodule CloudVision do
   %{requests: [%{features: [%{type: "IMAGE_PROPERTIES"}],
      image: %{source: %{gcsImageUri: "gs://dummy.appspot.com/cat.jpg"}}}]}
   """
-
   def build_params(img_path, opts), do:
     %{requests: [%{image: build_image(img_path, opts[:from]), features: build_features(opts[:features])}]}
 

lib/cloud_vision/client.ex

@@ -1,4 +1,6 @@
 defmodule CloudVision.Client do
+  @moduledoc false
+
   use HTTPoison.Base
   alias Goth.Token