ex_tldr: raise exceptions if request fail

If the request failed first check if it is because there is not internet
connection, if true, raise an NoInternetConnectionError, if it is not
the error, it raise an UnexpectedError and report to the user the error,
encouraging to report it in the official repository.

lib/ex_tldr.ex

@@ -79,8 +79,11 @@ defmodule ExTldr do
             IO.puts("Term not found on \"common\" pages.")
         end
 
-      {:error, %HTTPoison.Error{reason: reason}} ->
-        IO.inspect(reason)
+      {:error, %HTTPoison.Error{reason: reason}} when reason == :nxdomain ->
+        raise NoInternetConnectionError
+
+      {:error, %HTTPoison.Error{reason: reason}} when reason != :nxdomain ->
+        raise UnexpectedError, reason
     end
   end
 end