Add usage descrpiton, better for newbie

[csufuyi]

hi,

when I frist use TermRecord, When Type TermRecord -o xxx.html
I type something, and find xxx.html doesn't change.
after type exit, the html updated.
This confuse me so much, so please update the README.

Thanks!

[ghost]

Hi,
Can you update a detailed self-statement? Thank you!