adapters.elixire: use get/1 instead of get!/1

lib/adapters/elixire.ex

@@ -11,15 +11,25 @@ defmodule Elstat.Adapter.Elixire do
     addr = args.base_url
 
     req_start = :erlang.monotonic_time(:millisecond)
-    resp = HTTPoison.get!("#{addr}/api/hello")
+    status = HTTPoison.get("#{addr}/api/hello")
     req_end = :erlang.monotonic_time(:millisecond)
 
     delta = req_end - req_start
 
+    case status do
+      {:ok, resp} ->
         {:ok, {:map, %{
           status: resp.status_code == 200,
-              latency: delta,
+          latency: delta
         }}}
+      {:error, reason} ->
+        {:ok, {:map, %{
+          status: false,
+
+          # use drops to 0 as failure on conn
+          latency: 0
+        }}}
+    end
   end
 
   def transform_val({:map, %{status: status, latency: latency}}) do