fix docs

lib/file_system/backends/fs_inotify.ex

@@ -16,10 +16,10 @@ defmodule FileSystem.Backends.FSInotify do
   The default behaivour to find executable file is finding `inotifywait` from `$PATH`, there're two ways to custom it, useful when run `:file_system` with escript.
 
     * config with `config.exs`
-      `config :file_system, :fs_inotify, executable_file: "YOUR_EXECUTABLE_FILE_PATH"
+      `config :file_system, :fs_inotify, executable_file: "YOUR_EXECUTABLE_FILE_PATH"`
 
     * config with `FILESYSTEM_FSINOTIFY_EXECUTABLE_FILE` os environment
-      `FILESYSTEM_FSINOTIFY_EXECUTABLE_FILE=YOUR_EXECUTABLE_FILE_PATH`
+      FILESYSTEM_FSINOTIFY_EXECUTABLE_FILE=YOUR_EXECUTABLE_FILE_PATH
   """
 
   use GenServer

lib/file_system/backends/fs_mac.ex

@@ -27,10 +27,10 @@ defmodule FileSystem.Backends.FSMac do
   The default executable file is `mac_listener` in `priv` dir of `:file_system` application, there're two ways to custom it, useful when run `:file_system` with escript.
 
     * config with `config.exs`
-      `config :file_system, :fs_mac, executable_file: "YOUR_EXECUTABLE_FILE_PATH"
+      `config :file_system, :fs_mac, executable_file: "YOUR_EXECUTABLE_FILE_PATH"`
 
     * config with `FILESYSTEM_FSMAC_EXECUTABLE_FILE` os environment
-      `FILESYSTEM_FSMAC_EXECUTABLE_FILE=YOUR_EXECUTABLE_FILE_PATH`
+      FILESYSTEM_FSMAC_EXECUTABLE_FILE=YOUR_EXECUTABLE_FILE_PATH
   """
 
   use GenServer

lib/file_system/backends/fs_windows.ex

@@ -16,10 +16,10 @@ defmodule FileSystem.Backends.FSWindows do
   The default executable file is `inotifywait.exe` in `priv` dir of `:file_system` application, there're two ways to custom it, useful when run `:file_system` with escript.
 
     * config with `config.exs`
-      `config :file_system, :fs_windows, executable_file: "YOUR_EXECUTABLE_FILE_PATH"
+      `config :file_system, :fs_windows, executable_file: "YOUR_EXECUTABLE_FILE_PATH"`
 
     * config with `FILESYSTEM_FSWINDOWS_EXECUTABLE_FILE` os environment
-      `FILESYSTEM_FSWINDOWS_EXECUTABLE_FILE=YOUR_EXECUTABLE_FILE_PATH`
+      FILESYSTEM_FSWINDOWS_EXECUTABLE_FILE=YOUR_EXECUTABLE_FILE_PATH
   """
 
   use GenServer