add wubot to exchange field for inlet_test case

[jcwarner]

Please modify ROMS/External/coupling_inlet_test.in from

Nexport(waves) = 5

Export(waves) = Wdir \

Wamp \ Wlen \ Wptop \ Wpbot

Nimport(ocean) = 5

Import(ocean) = Wdir \

Wamp \ Wlen \ Wptop \ Wpbot

to

Nexport(waves) = 6

Export(waves) = Wdir \

Wamp \ Wlen \ Wptop \ Wpbot \ Wubot

Nimport(ocean) = 6

Import(ocean) = Wdir \

Wamp \ Wlen \ Wptop \ Wpbot \ Wubot

This app uses the SSW BBL and requires the Bottom orbital velocity to be sent from Waves to Ocean.