pkgng/pkgng — pull request #420 by smortex (2013-01-25 09:48:42+00:00)
Title: Fail consistently with non-existing packages

Make error reporting more consistent with non-existing packages.

Before:
1. `pkg install non-existent`
- Displays that the "non-existent" package does not exist;
- returns 70 (EX_SOFTWARE).
2. `pkg install apache22 non-existent`
- Displays that the "non-existent" package does not exist (however
it's harder to catch it);
- Installs apache22;
- returns 0 (success while the result is not what we expect).

This provide consistent failure (as in 1) when some packages are not
found.

While here, add a missing line break at the end of the error message for
inexistent packages.