Allow user to control output emitted by `hmds`

[Kevin Ushey]

E.g.

> hmds(matrix())
0 : 0 : 9.154231 
0 : 1 : 1.295180 
0 : 2 : 0.909164 
0 : 3 : 7.521004 
0 : 4 : 7.515656 
0 : 5 : 6.444834 
0 : 6 : 2.650794 
0 : 7 : 3.501593 
0 : 8 : 8.213786 
0 : 9 : 1.268850 
0 : 10 : 4.044897 
0 : 11 : 5.629833 
0 : 12 : 7.183209 
0 : 13 : 4.674137 
0 : 14 : 5.216217 
0 : 15 : 4.089559 
0 : 16 : 2.277564 
0 : 17 : 8.733508 
0 : 18 : 0.132038 
0 : 19 : 9.495266 
0 : 20 : 0.630379 
0 : 21 : 4.039999 
0 : 22 : 3.874295 
0 : 23 : 1.651352 
0 : 24 : 5.504311 
0 : 25 : 1.824779 
0 : 26 : 0.067227 
0 : 27 : 5.568614 
0 : 28 : 2.412821 
0 : 29 : 1.006876 
0 : 30 : 2.101734 
0 : 31 : 4.298240 
0 : 32 : 2.362230 
0 : 33 : 9.964386 
0 : 34 : 8.526113 
0 : 35 : 0.316426 
0 : 36 : 9.567611 
0 : 37 : 3.220868 
0 : 38 : 6.748602 
0 : 39 : 0.109211 
0 : 40 : 6.364845 
0 : 41 : 9.364899 
0 : 42 : 6.283575 
0 : 43 : 5.715547 
0 : 44 : 0.996311 
0 : 45 : 7.619263 
0 : 46 : 5.049326 
0 : 47 : 0.778688 
0 : 48 : 3.755725 
0 : 49 : 7.531476 
count : 1000 
      item :       item : input distance : output distance
input data distance : 0.000000
output data distance : 0.000000
count:0
         [,1]    [,2]      [,3]     [,4]     [,5]     [,6]     [,7]     [,8]     [,9]   [,10]
[1,] 9.154231 1.29518 0.9091641 7.521004 7.515656 6.444834 2.650794 3.501593 8.213786 1.26885
        [,11]    [,12]    [,13]    [,14]    [,15]    [,16]    [,17]    [,18]     [,19]    [,20]
[1,] 4.044897 5.629833 7.183209 4.674137 5.216217 4.089559 2.277564 8.733508 0.1320378 9.495266
         [,21]    [,22]    [,23]    [,24]    [,25]    [,26]      [,27]    [,28]    [,29]    [,30]
[1,] 0.6303789 4.039999 3.874295 1.651352 5.504311 1.824779 0.06722711 5.568614 2.412821 1.006876
        [,31]   [,32]   [,33]    [,34]    [,35]     [,36]    [,37]    [,38]    [,39]     [,40]
[1,] 2.101734 4.29824 2.36223 9.964386 8.526113 0.3164265 9.567611 3.220868 6.748602 0.1092108
        [,41]    [,42]    [,43]    [,44]     [,45]    [,46]    [,47]     [,48]    [,49]    [,50]
[1,] 6.364845 9.364899 6.283575 5.715547 0.9963105 7.619263 5.049326 0.7786881 3.755725 7.531476

The function should probably provide a verbose / quiet argument or similar, controlling whether output is printed to the console. (Also: is this producing a sensible result for a matrix of this form?)