installed_progs.t: Add 8 more programs

55a7455a-47db-11e4-a784-c80aa9e67bbd
installed_progs.t: installed(): Remove unused variable

1ad85de0-47dd-11e4-ac93-c80aa9e67bbd
installed_progs.t: Specify path to some coreutils commands

After I created the stderr/stdout functionality (a future commit), some
coreutils tests started to fail because they also were available in
bash(1). To get around this, some commands are specified with full path,
and this is stripped away in coreutils().

7a52ae3c-47e3-11e4-b53f-c80aa9e67bbd
installed_progs.t: installed(): Add argument for stderr/stdout/both

Before this, stderr was redirected to stdout and both streams were
checked at the same time. Some programs insist on being difficult,
though, for example sending lots of rubbish to stderr while the version
info (which is not very informative) is sent to stdout. Because I'm so
damn polite I won't write the name of the program that made me do this.
It's not like I'll add it in the next commit or anything.

6be3dad6-47e5-11e4-9c58-c80aa9e67bbd
installed_progs.t: Add shutter

c67ce9b0-47e5-11e4-907f-c80aa9e67bbd