The balance command's --format option (in single-column mode) can now
adjust the rendering of multi-line strings, such as amounts with multiple
commodities. To control this, begin the format string with one of:
%_ - renders on multiple lines, bottom-aligned (the default)
%^ - renders on multiple lines, top-aligned
%, - render on one line, comma-separated
Also the final total (and the line above it) now adapt themselves to a
custom format.
