check for exclude directory
implement base of watcher event
WatcherThread: don't create writer, ask for it
App: create IndexReader instance only once
add exclude dir
commit settings changed when closing daemon
add include directory command
refactor to a better name
remove useless method
Merge branch 'master' into watcher-event

Conflicts:
	src/main/java/com/mee/ir/App.java
update if file modified
WatcherThread: ask for Tokenizer
WatcherThread: complete task for modify & delete