Proper alignment threatment in read and generate

For O_DIRECT to work properly the length and file offset arguments for pread should be aligned to 4096 chunks. Otherwise, it will fail with EINVAL.

To properly align the accesses we have to have 1) item count to be divisible by 512 (count of doubles in 4096 bytes) and 2) file offset and count to also be divisible by 512.

The main changes are in create-floats.c, where offsets and counts are computed. We reuse previous code that computed unaligned accesses. We just supply item count divided by 512 and then multiply result by 512.

The same changes apply to ddp-erlang-style.hs. Master computes offsets and counts by using functions to compute aligned values. The functions reside in DNA.Channel.File module, along with default alignment value (512 doubles or 4096 bytes).

Master also has a command line argument -a|--alignmentt to specify alignments in case they change.

All arguments to file reading functions are now Int64 (long in C parlance).

SimpleLocalnet don't display excessive error messages.

ddp-erlang-style now displays it's version to prevent confusion in running old code.