latest load_runs
Merge branch 'master' of http://github.org/dcherian/eddyshelf
convert eddy.vormask to logical to save memory. Also added flag read_zeta to control whether zeta is read
convert ssh mask to logicals rather than deleting it to save space
added read_zeta and call it in a few places since i no longer read zeta in by default. this was done to save time
added hovmoeller diagram for along-shore velocity over the shelf
added read_zeta and initializing masks to empty arrays