Add documentation and example to hdfimport for creating a 2D dataset

[bmribler]

Original issue: HDFFR-1344

The hdfimport tool documentation does not clearly define how you should create a 2D dataset. You have to add a 3rd dimension of 1 after "TEXT" or the 2D dataset is not created properly.

For example, this creates a 2D dataset that is 4x3:

TEXT
1
4
3
1
0
1 2 3 4
1 2 3
1 1 0
1 1 0
0 0 0
1 1 0

Also, it would be very helpful if there were example input files (with different datatypes) in the documentation as well as in the hdfimport usage statement, to help users understand how to use it.

Here is another example:

TEXT
1
10
10
2686
2409
180 181 182 183 184 185 186 187 188 189
280 281 282 283 284 285 286 287 288 289
2409 2438 2468 2500 2538 2569 2595 2611 2604 2586
2416 2442 2483 2513 2549 2582 2612 2635 2638 2619
2425 2448 2495 2558 2593 2628 2656 2665 2645 2626
2444 2468 2500 2531 2564 2604 2646 2674 2682 2666
2463 2485 2512 2542 2574 2611 2651 2678 2686 2676
2463 2485 2512 2542 2574 2611 2651 2678 2686 2676
2444 2468 2500 2531 2564 2604 2646 2674 2682 2666
2425 2448 2495 2558 2593 2628 2656 2665 2645 2626
2416 2442 2483 2513 2549 2582 2612 2635 2638 2619
2409 2438 2468 2500 2538 2569 2595 2611 2604 2586

Here is a 3D example:

TEXT
2 2 5
.98 .90
.98 .96
.98 .96
.98 .96 .94 .92 .90
.42 .31 .24 .32 .29
.31 .32 .32 .43 .28
.30 .30 .30 .30 .30
.30 .30 .30 .30 .30