Remove jquery-ui customization in network

Network UI is built with jquery-ui widgets.
To get network to match kimchi ui style.
jquery-ui widgets style is customized there.

now, we have jquery-ui widgets customized formally by
following offcial jquery-ui themeing structure.

remove customization in network, leverage the
formal cusomization.

Signed-off-by: Yu Xin Huo <huoyuxin@linux.vnet.ibm.com>