update: Updated metadata missing in .pm files

* Updated a few metadata items that were missing in .pm files. These
  might be simply regarded as typos and thus, this commit is of very
  small importance.

Signed-off-by: mr.Shu <mr@shu.io>
Merge pull request #705 from duckduckgo/mrshu/fix-metadata

update: Updated metadata missing in .pm files