adminActivityLog: update "Possible Servlets Requests:" section under the search box #1224

for #1224 
pass the number of columns as a parameter. As much as possible, the data required by the method should be passed in as parameters. That makes the method signature more intuitive and the method more testable. Otherwise the reader will be puzzled how this method is supposed to create the HTML without knowing the number of columns. To find the answer, he has to read and understand the whole method, which is a waste of time.