Tested: ABC for SV model - changing summary statistics

The summary statistics are changed to the whole dataset, and the graph
of results is added.
Remark 1: Changing to the whole dataset improves the performance. The
performance of sigma now is much better than that under the previous
summaries.
Remark 2: The variance of IS proposal is shrinking and the mean is
moving to the truth in the adaptive step. The performances for rho and
sigma are better than rej ABC,  although the performance for estimating
alpha is not better than the rej ABC.