Added figure captions to capture rate function. Added two new functions ...

Added figure captions to capture rate function. 

Added two new functions I regularly use locally: MeanResTime which plots residence time distribution and fits with single exponential and NumberOfEvents, a function which counts number of files which fit specific query in the DB.

Mean ResTime will be updated in near future to include additional features existing in legacy function such as outputting a table of the fitting results. In future, it would be beneficial to perform a weighted fit.