Change sort_parameters `runLength` from a stream_size_type to a memory_size_type.

The run length must be a buffer size that we can keep in main memory, so
on 32-bit systems it does not make sense to have a runLength greater
than 2^32.
Change progress_indicator_arrow::m_indicatorLength from stream_size_type to memory_size_type.
Fix unused variable warnings in ami::stream.
Switch linear_memory_base::memory_usage from a stream_size_type to a memory_size_type.
Fix counter types in test/speed_regression/fractile.h
test/speed_regression/numbergen.cpp: Supply correct integer type to mt19937.
ut-external_priority_queue: Supply float instead of double to tpie::priority_queue.
progress_indicator_arrow.h: The arrow length should be a memory_size_type.
Fixup runLength change.