git fetch failure for net-dav + work-around

[notklaatu]

During the bundle install step:

Retrying git fetch --force --quiet --tags "/home/notklaatu/.bundle/ \
cache/git/net_dav-cfd3539cb697ebad3b54ee22c85d520206c52405" \
due to error (3/4): Bundler::Source::Git::GitCommandError Git error: \
command `git fetch --force --quiet --tags "/home/notklaatu/.bundle/ \
cache/git/net_dav-cfd3539cb697ebad3b54ee22c85d520206c52405"` \
in directory /var/lib/gems/2.1.0/bundler/gems/net_dav-615797fa55a7 has failed.

If this error persists you could try removing the cache directory 
'/home/notklaatu/.bundle/cache/git/ \
net_dav-cfd3539cb697ebad3b54ee22c85d520206c52405' \
error: cannot open .git/FETCH_HEAD: Permission denied

Removing the net-dav line from the Gemfile and installing net-dav manually succeeds.