DOC: Change concise example to be run_fissa

README.rst

@@ -56,11 +56,10 @@ A concise example of how to use FISSA is as follows.
 
     import fissa
 
-    experiment = fissa.Experiment('path/to/tiffs', 'path/to/rois.zip', 'experiment_name')
-    experiment.separate()
+    result = fissa.run_fissa('path/to/tiffs', 'path/to/rois.zip')
 
-    # The separated time series data is now available as experiment.result
-    experiment.result[roi_index, tiff_index][0, :]
+    # The decontaminated time series is now available as
+    # result[roi_index, tiff_index][0, :]
 
 We also have several example notebooks for a basic workflow and more complicated
 workflows where FISSA needs to interact with the outputs of other two-photon