update readme for :run_at_start

README.md

@@ -57,16 +57,17 @@ the directory specified by the `:from` option to that specified by the
 ### List of available options:
 
 ``` ruby
-:from     => 'source' # directory to copy files from
-:to       => 'target' # directory or glob to copy files to; string or array
-:glob     => :newest  # how to handle globs; default: :all
-                      #   :newest - copy to only the newest directory
-                      #   :all    - copy to all directories
-:mkpath   => true     # create directories in target when full target path
-                      # does not exist; default: false
-:delete   => true     # delete files from target directories; default: false
-:verbose  => true     # log all operations as info messages; default: false
-:absolute => true     # allow absolute paths for :to; default: false
+:from         => 'source' # directory to copy files from
+:to           => 'target' # directory or glob to copy files to; string or array
+:glob         => :newest  # how to handle globs; default: :all
+                          #   :newest - copy to only the newest directory
+                          #   :all    - copy to all directories
+:mkpath       => true     # create directories in target when full target path
+                          # does not exist; default: false
+:delete       => true     # delete files from target directories; default: false
+:verbose      => true     # log all operations as info messages; default: false
+:absolute     => true     # allow absolute paths for :to; default: false
+:run_at_start => true     # copy all files at startup (does not remove any files)
 ```
 
 ## Watchers