Update documentation for the database type

See #9

README.md

@@ -67,6 +67,7 @@ configuration file. You can find the configuration file example on
 | TOGLACIER_AWS_VAULT_NAME         | AWS vault name                          |
 | TOGLACIER_PATHS                  | Paths to backup (separated by comma)    |
 | TOGLACIER_AUDIT                  | Path where we keep track of the backups |
+| TOGLACIER_DATABASE_TYPE          | Local backup storage strategy           |
 | TOGLACIER_LOG_FILE               | File where all events are written       |
 | TOGLACIER_LOG_LEVEL              | Verbosity of the logger                 |
 | TOGLACIER_KEEP_BACKUPS           | Number of backups to keep (default 10)  |
@@ -107,10 +108,13 @@ the variables `TOGLACIER_AWS_ACCOUNT_ID`, `TOGLACIER_AWS_ACCESS_KEY_ID`,
 file. The tool will detect an encrypted value when it starts with the label
 `encrypted:`.
 
-The audit file that keeps track of all backups has the format bellow. It's a
-good idea to periodically copy this audit file somewhere else, so if you lose
-your server you can recover the files faster from the AWS Glacier (don't need
-to wait for the inventory).
+For keeping track of the backups locally you can choose `boltdb`
+([BoltDB](https://github.com/boltdb/bolt)) or `auditfile` in the
+`TOGLACIER_DATABASE_TYPE` variable. By default `boltdb` is used. If you choose
+the audit file, as it is a human readable and a technology free solution, the
+format is defined bellow. It's a good idea to periodically copy the audit file
+or the BoltDB file somewhere else, so if you lose your server you can recover
+the files faster from the AWS Glacier (don't need to wait for the inventory).
 
     [datetime] [vaultName] [archiveID] [checksum]
 
@@ -135,7 +139,9 @@ TOGLACIER_AWS_REGION="us-east-1" \
 TOGLACIER_AWS_VAULT_NAME="backup" \
 TOGLACIER_PATHS="/usr/local/important-files-1,/usr/local/important-files-2" \
 TOGLACIER_AUDIT="/var/log/toglacier/audit.log" \
+TOGLACIER_DATABASE_TYPE="boltdb" \
 TOGLACIER_LOG_FILE="/var/log/toglacier/toglacier.log" \
+TOGLACIER_LOG_LEVEL="error" \
 TOGLACIER_KEEP_BACKUPS="10" \
 TOGLACIER_BACKUP_SECRET="encrypted:/lFK9sxAXAL8CuM1GYwGsdj4UJQYEQ==" \
 TOGLACIER_EMAIL_SERVER="smtp.example.com" \
@@ -195,7 +201,9 @@ c:\> nssm.exe set toglacier AppEnvironmentExtra ^
   TOGLACIER_AWS_VAULT_NAME=backup ^
   TOGLACIER_PATHS=c:\data\important-files-1,c:\data\important-files-2 ^
   TOGLACIER_AUDIT=c:\log\toglacier\audit.log ^
+  TOGLACIER_DATABASE_TYPE=boltdb ^
   TOGLACIER_LOG_FILE=c:\log\toglacier\toglacier.log ^
+  TOGLACIER_LOG_LEVEL=error ^
   TOGLACIER_KEEP_BACKUPS=10 ^
   TOGLACIER_BACKUP_SECRET=encrypted:/lFK9sxAXAL8CuM1GYwGsdj4UJQYEQ== ^
   TOGLACIER_EMAIL_SERVER=smtp.example.com ^