Creation of simple_moving_average example
creation of matrix_transpose example
Add perf tests for exclusive_scan

        - perf_exclusive_scan for Boost.Compute
        - perf_thrust_exclusive_scan for thrust
Update perf_partial_sum : no internal allocation and copy

Calling the partial_sum algorithm with the same input/output
buffer leads to an internal allocation and copy.
Merge pull request #111 from banche/develop

matrix transpose and simple moving average examples + exclusive_scan perf tests