[Enhancement] Add Apprise support (#170)

* [WIP] add settings sidebar entry and placeholder page

* [WIP] added placeholder UI and logic for settings form

* Added column and UI for apprise server

* Add some tests

* Added placeholder command runner for apprise

* [WIP] Adding apprise package

* Added apprise command runner

* Hooked up apprise notification module

* Ensured apprise was running in verbose mode

* Updated wording of apprise notification

* Added apprise to README

lib/pinchflat/utils/cli_utils.ex

@@ -0,0 +1,48 @@
+defmodule Pinchflat.Utils.CliUtils do
+  @moduledoc """
+  Utility methods for working with CLI executables
+  """
+
+  alias Pinchflat.Utils.StringUtils
+
+  @doc """
+  Parses a list of command options into a list of strings suitable for passing to
+  `System.cmd/3`.
+
+  We want to satisfy the following behaviours:
+    1. If the key is an atom, convert it to a string and convert it to kebab case (for convenience)
+    2. If the key is a string, assume we want it as-is and don't convert it
+    3. If the key is accompanied by a value, append the value to the list
+    4. If the key is not accompanied by a value, assume it's a flag and PREpend it to the list
+
+  Returns [binary()]
+  """
+  def parse_options(command_opts) do
+    command_opts
+    |> List.wrap()
+    |> Enum.reduce([], &parse_option/2)
+  end
+
+  defp parse_option({k, v}, acc) when is_atom(k) do
+    stringified_key = StringUtils.to_kebab_case(Atom.to_string(k))
+
+    parse_option({"--#{stringified_key}", v}, acc)
+  end
+
+  defp parse_option({k, v}, acc) when is_binary(k) do
+    acc ++ [k, to_string(v)]
+  end
+
+  defp parse_option(arg, acc) when is_atom(arg) do
+    stringified_arg =
+      arg
+      |> Atom.to_string()
+      |> StringUtils.to_kebab_case()
+
+    parse_option("--#{stringified_arg}", acc)
+  end
+
+  defp parse_option(arg, acc) when is_binary(arg) do
+    acc ++ [arg]
+  end
+end