Remove changeset_revision and toolshed attributes from <repository> in all tool_dependencies.xml files.

This was accomplished with the following command:

find . -name tool_dependencies.xml -print0 | xargs -0 sed -i -e 's/ changeset_revision="[a-z0-9]\{1,\}"//g' -e 's/ toolshed="https\{0,1\}:\/\/toolshed.g2.bx.psu.edu\/\{0,1\}"//g'