Revert "fix #101 by documenting it"

This reverts commit afe82178d62f24d30cb197e013e1deb3e6fbf830.

Problem was already [documented][1]

[1]: https://github.com/MarcWeber/vim-addon-manager/blob/9ed80116575eaec014f9d3538dc91e2271eeea66/doc/vim-addon-manager-additional-documentation.txt#L869