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- use a custom lockfile implementation for single instance check in Linux (issue 27)
- print reason when exiting program due to another instance already running (issue 27)
- fix setting program to run at startup in newer Windows (issue 28)
- tweak escaping special characters for regex in heatmap page application search
- create new database file with default ownership permissions in Linux
- bundle licenses for included third-party software in released binaries
- exclude blank database from source distributions, to avoid overwriting it on upgrade