Hardcoded database path

[DragoonAethis]

Here: https://github.com/autyzm-pg/friendly-plans-link/blob/master/backupper-core/src/main/java/pl/gda/pg/eti/autyzm/backupper/core/Config.java

• Some Android versions prevent accessing storage via /storage/sdcard0 (most devices have that linked, but eg under Android 6.0 sdcard0 is replaced with a file system UUID. See this: https://android.stackexchange.com/questions/14105/how-can-i-determine-storage-directory-from-adb - adb shell echo $EXTERNAL_STORAGE provides the real path, regardless of the Android version running on the device.
• Newer Android versions (4.4+) use SQLite with journals. If a database write wasn't completed, the "main" database file is partially written to, but the journal contains the data necessary to complete the transaction (even if it's just a simple insert) and make the database usable. Therefore backing up just the main database file (without commments2.db-journal) may occasionally back up a broken database - checking if the journal exists (and backing it up if that's the case) is required.
• Android apps should use the private application storage to store databases (think /data/data/org.application.etc/databases or /path/to/primary/storage/Android/data/org.application.etc/databases). The second method is preferred if a database file should be shared between apps and accessible R/W via ADB.