Fix wide character output for download progress

Now that we have a Chinese translation, all of the problems with new
character sets crop up. Assumptions were made in the past that all
characters occupied one column, which is not true with a Chinese character
set. In addition, the download code even failed on such things as 'ö', which
is two bytes wide but only 1 column.

This code will need to also be ported to the add/remove/upgrade/conflicts
progress printouts.

Note that the tests below try to incorporate a number of things:
1. download filenames too long to fit
2. download filenames cut off in the middle of a multibyte sequence
3. download filenames incorporating multicolumn chars
4. download filenames incorporating multibyte, single-column chars
5. 'plain' download filenames that have always worked

Before:
:: 正在同步软件包数据库……
 正在解决倚赖��...    0.0K  199.8K/s 00:00:00 [-----------------] 100%
错误：无法升级正在解决倚赖关系junköëjunköëjunköëäää (未预计的系统错误)
 正在解决倚赖��...    0.0K  308.4K/s 00:00:00 [-----------------] 100%
错误：无法升级正在解决倚赖关系 (未预计的系统错误)
 junköëä                 0.0K  390.6K/s 00:00:00 [-----------------] 100%
错误：无法升级junköëä (未预计的系统错误)
 pacman-git                 0.5K    4.3M/s 00:00:00 [-----------------] 100%
本地数据库已是最新的

After:
:: 正在同步软件包数据库……
 正在解决倚赖关系jun...     0.0K   89.7K/s 00:00:00 [-----------------] 100%
错误：无法升级正在解决倚赖关系junköëjunköëjunköëäää (未预计的系统错误)
 正在解决倚赖关系           0.0K  147.7K/s 00:00:00 [-----------------] 100%
错误：无法升级正在解决倚赖关系 (未预计的系统错误)
 junköëä                    0.0K  156.9K/s 00:00:00 [-----------------] 100%
错误：无法升级junköëä (未预计的系统错误)
 pacman-git                 0.5K 1515.9K/s 00:00:00 [-----------------] 100%
本地数据库已是最新的

Signed-off-by: Dan McGee <dan@archlinux.org>

0 files changed, 0 insertions, 0 deletions