unshelve: abort on using --keep and --interactive together
I am working on making interactive mode support `--keep` flag. Until
we support the usage of `--interactive` and `--keep` together, let
us abort on it.
Differential Revision: https://phab.mercurial-scm.org/D6699
$ rm -rf a
$ hg init a
$ cd a
$ echo a > a
$ hg ci -Am0
adding a
$ hg tag t1 # 1
$ hg tag --remove t1 # 2
$ hg co 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg tag -f -r0 t1
$ hg tags
tip 3:a49829c4fc11
t1 0:f7b1eb17ad24
$ cd ..