Typo in hydro.py swash calculation for Stockdon runup?

[savannahdevoe]

There appears to be a typo in the swash calculation in hydro.py calc_runup_stockdon.

Line 797 (similarly line 813) gives:
sigma_s = np.sqrt(Ho * Lo * (0.563 * (beta * beta) + 0.0004)) * nsigma / 2 / 2

Should this instead be:
sigma_s = np.sqrt(Ho * Lo * (0.563 * (beta * beta) + 0.004)) * nsigma / 2 / 2

The order of magnitude difference in the factor 0.004 could cause discrepancies in estimated swash on the order of several cm. E.g., for Ho = 1 m, Lo = 100 m, beta = 0.05 (nsigma = 2 for R2 and Iribarren = 0.5) would give sigma_s = 0.21 m for 0.0004 versus 0.37 m for 0.004.

Thank you!