Bacterial Leaf Spot Or Tomato Leaf Spot

This looks like its probably a leaf spot disease, either Bacterial or fungal Septoria leaf spot; both of them are spread by splashing water on leaves. We’ve included some web links about them for your reference, but the only way to ID plant disease for certain is to have a pathologist test the tissue. You can take samples of all affected plant parts (sealed in a bag) to your local Dept of Agriculture office and they will reply to you by mail. Provide them with as much info about the plant environment as possible. In the meantime, you may choose to remove the most affected leaves, and we recommend you review the info provided in the weblink about caring for tomato plants.
http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/tomato.html