This is the package signature as generated by The GnuPG. This signature identifies the party that created the package. By verifying it you are sure that the package coming from a trustworty person or organization.
Here is the package signature:
-----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iEYEABECAAYFAlAw4UMACgkQqesEzEdeXBEPRwCgogd7pf7xl+BL4uzI4IUQszE1 xhgAnAi1dqdgZVZf9t+Z3XMoo0/YVso4 =d7K8 -----END PGP SIGNATURE-----
You can save this signature in a text file (e.g. libvpx-1.1.0-i686-1gds.txz.asc) in the same directory where the package file (libvpx-1.1.0-i686-1gds.txz) resides and you can verify it by issuing the following command:
gpg --verify libvpx-1.1.0-i686-1gds.txz.asc
NOTE: You need to import the public key of SlackPack first:
gpg --import KEY