Logging stimuli

[ajsbeckett]

Add code to create (in no particular order):

• local parameter file (e.g pickle) so parameters can be loaded/saved/repeated easily
• txt parameter file to show record of when certain stimulus parameters were ran for bookkeeping purposes
• automatic generation of stim timing files (e.g 1D) - either just based from parameters or from explicit stimulus loggng

visualLoc.py has a rough version of #2 (text file) for now