If you have a prompt preceded by a new line, you'll get a line full of spaces instead of an empty line above your prompt. This doesn't make a difference in normal usage, but copying and pasting your terminal log becomes a pain. This commit clears that line, making it an actual empty line.
Rather than trying to detect Unicode support from the environment, check
the printable width of characters in the current locale before deciding
on whether to use them.
Closes#1927.
This change moves source files into a src/ directory,
and puts object files into an obj/ directory. The Makefile
and xcode project are updated accordingly.
Fixes#1866
