add signature setting

For multiple users it helps to
keep track about who did what.

app/src/main/java/it/danieleverducci/lunatracker/repository/LocalSettingsRepository.kt

@@ -14,6 +14,7 @@ class LocalSettingsRepository(val context: Context) {
         const val SHARED_PREFS_DAV_USER = "webdav_user"
         const val SHARED_PREFS_DAV_PASS = "webdav_password"
         const val SHARED_PREFS_NO_BREASTFEEDING = "no_breastfeeding"
+        const val SHARED_PREFS_SIGNATURE = "signature"
     }
     enum class DATA_REPO {LOCAL_FILE, WEBDAV}
     val sharedPreferences: SharedPreferences
@@ -30,6 +31,14 @@ class LocalSettingsRepository(val context: Context) {
         return sharedPreferences.getInt(SHARED_PREFS_BB_CONTENT, 1)
     }
 
+    fun saveSignature(content: String) {
+        sharedPreferences.edit { putString(SHARED_PREFS_SIGNATURE, content) }
+    }
+
+    fun loadSignature(): String {
+        return sharedPreferences.getString(SHARED_PREFS_SIGNATURE, "") ?: ""
+    }
+
     fun saveNoBreastfeeding(content: Boolean) {
         sharedPreferences.edit { putBoolean(SHARED_PREFS_NO_BREASTFEEDING, content) }
     }