Using "hledgerdev" was a hack to help ensure that tests used a fresh
developer build by default. Now they specify "hledger" again, which fits
better with stack. It's up to the tester to make sure the desired
executable is first in PATH or specified with -w. (Note a couple of
tests currently don't obey -w and will always run "hledger", see addons.test).
Amount display styles have been reworked a bit; they are now calculated
after journal parsing, not during it. This allows the fix for #196:
we now search through the amounts until a decimal point is detected,
instead of just looking at the first one; likewise for digit groups.
Digit groups are now implemented with a better type.
Digit group size detection has been improved a little:
1000,000 now gives group sizes [3,4,4,...], not [3,3,...], and
10,000 gives groups sizes [3,3,...] not [3,2,2,..].
(To get [3,2,2,...] you'd use eg 00,00,000.)
There are still some old (or new ?) issues; I don't think we handle
inconsistent decimal points & digit groups too well. But for now all
tests pass.