initialization fixes to --progress, now more logical + test suite and references updates

This fixes the update progress dumps to behave more rationally:

1) Initialization of first `dump_interval` is 1.0 rather than exp(1) which used to print example 3 first
2) Doubling `dump_interval` now results in 1,2,4,8,...
3) progress updates are printed if `weighted_examples` equals or exceeds `dump_interval` (condition was strictly "greater than" which was inaccurate, leading to off-by-one inconsistencies)
4) The update of `dump_interval` which could diverge over time from the printed example is now synchronized with the printing whenever printing happens, so the printing gaps are not becoming seemingly semi-random at times.
5) In additive progress dumps, we start at 0, so: --progress 10 means: 10,20,30,40,...
6) in multiplicative progress dumps, we start at 1.0, so --progress 2.0 (default) means: 1,2,4,8,16,...

I went through all the references one by one and confirmed they 1) make sense and 2) don't introduce any new issue.

Fully updated the references to pass the test suite.