update readme
update jade tag

by following jade's suggestion

    Implicit textOnly for `script` and `style` is deprecated.  Use
    `script.` or `style.` instead.
trivial code clean

remove invisible white-space
readme: add som terminologies
sitting: speficy controller in partial page

let the router just specify 'sitting.jade' will be used for
url path '/sitting'. And let sitting.jade specify its own
controller - LYSitting.
change file permission to 644
rename existed sass/scss

and clean up
art: add AliceWei's effort
art: make navbar activable
art: restrict height of fb button
art: minor change to active Alice's design

sass will generate some debug-info css and that effect appearance
when we are in development mode.

force specify background-image to avoid it.
add closing brace
art: add collapse button to navbar
clean up navbar
art: update sitting page

to reach Alice's deisgn
sitting: simply parse meta data