tests/test-ancestor.py.out

ui: add new config option for help text width

Before this patch, when printing help text using `hg help`, or `hg log -h`,
the output will wrap at 78 chars even if the user has a bigger terminal width
and there is no config option to change it, making the experience different
from the commonly used `man` tool.

This patch introduces a new config option `ui.textwidth`, which replaces the
hardcoded number. It's set to 78 by default to maintain compatibility. When
set to 0, `hg help` will behave more like `man`.

% lazy ancestor set for [], stoprev = 0, inclusive = False
membership: []
iteration:  []
% lazy ancestor set for [11, 13], stoprev = 0, inclusive = False
membership: [7, 8, 3, 4, 1, 0]
iteration:  [3, 7, 8, 1, 4, 0, 2]
% lazy ancestor set for [1, 3], stoprev = 0, inclusive = False
membership: [1, 0]
iteration:  [0, 1]
% lazy ancestor set for [11, 13], stoprev = 0, inclusive = True
membership: [11, 13, 7, 8, 3, 4, 1, 0]
iteration:  [11, 13, 3, 7, 8, 1, 4, 0, 2]
% lazy ancestor set for [11, 13], stoprev = 6, inclusive = False
membership: [7, 8]
iteration:  [7, 8]
% lazy ancestor set for [11, 13], stoprev = 6, inclusive = True
membership: [11, 13, 7, 8]
iteration:  [11, 13, 7, 8]