track files with UTF-8 filename issues
building multiple release versions
removing Deployment from repo
Handle nil values for Simplenote-synced content, tags, systemTags

If we receive nil for content, tags, or systemTags, replace it with an empty string, empty array, or empty array, respectively, rather than trying to store a nil in the NSDictionary.

Fixes #200
switched some calls from @jtamboli's pull request to literals