install: use -L as well as -e to check for existence

Signed-off-by: Christopher Larson <kergoth@gmail.com>
shell/login: export OSTYPE/LOGNAME/HOSTNAME

Signed-off-by: Christopher Larson <kergoth@gmail.com>
vim: use git uri for bundles

Signed-off-by: Christopher Larson <kergoth@gmail.com>