Fixes Issue #14 (iCloud directory not tried)

The directory option containing the DayOne location for iCloud was overwritten with the Dropbox location regardless of the fact, that the iCloud location existed or not. Somehow this bug was introduced in the feature addition itself in 544f7df.
Merge pull request #16 from enplotz/fix-dir-auto

Fixes Issue #14 (iCloud directory not tried)