Smack labels for databases are restored after database removal

Smack labels for databases are restored after database removal

[Issue#] N/A
[Feature/Bug] N/A
[Problem] After calling wrt_reset_all.sh wrt database labels are reset to "_"
[Cause] Db files are removed and created with default label
[Solution] Old label is stored and applied to newly created files

[Verification]
1.Check /opt/dbspace/.wrt.db* labels with chsmack [filename]. It should be
"wrt-commons::db_wrt"
2.Run wrt_reset_all.sh. Check labels again. They should be the same.

Change-Id: I885638d482c921fadea0a74d773ce8a548387483