Fix a thinko in scientific notation usage: 10e -> 1e in num literals
pplot: Move markevery style setting out of _style_strategy() as it's dataset-specific
PortfolioDataSets: algds_dimfunc(), stratds_dimfunc() utilities

Also a maxevals() utility.
PortfolioDataSets.oracle(): Rewrite to return the actually best algorithm
New plot type ert_by_target()