python, swig: fix bugs and restore Python ergonomics after libnvmf_context refactor#3291

martin-belanger wants to merge 3 commits intolinux-nvme:masterlinux-nvme/nvme-cli:masterfrom

martin-belanger:swig-python-bindings-fixmartin-belanger/nvme-cli:swig-python-bindings-fixCopy head branch name to clipboard