Fix UpdateVcsWatchTask to store vcswatch data using another PackageData key
Closes #29 (closed)
Notice that although this code will avoid future runnings to save changelog_version into vcs_extra_links, it will not remove the wrong package infos already stored in the production env's database (which contains the data related to changelog_version).
So, unless you have another suggestion, it will require you to remove the current 'vcs_extra_links' PackageData from the database and run the UpdateVcsWatchTask again.