save_state: save as file or and/or git commit as configured
rename restore_state() -> restore_state_from_file()
Joels current namarc-home
Persistence.p: new     restore_state_from_vcs()
               fix     git_create_branch(): branch from correct commit (not current HEAD)
Project.p: load_project(): retrieve settings from vcs
EffectChain.p: fix AUTOLOAD error (add null DESTROY method)
namarc: disable autosave
namarc-home: remove save_as_file option
save_state foo.json saves to file foo.json
save allows save foo.json
new logic for dispatching "save something" to serialization and VCS back ends
restore_state_from_file strips .json
Project: restore_state() uses argument .json
extension to set restore from named serialization file
restore_state_from_file(): provide full path to get_newest() fixing "get_state foo.json"
remove nonfunctional -D option
12_nama.t: fix git-related test failure; diag() output is conditional on $debug
remove duplicate var declaration
::File class: add DESTROY method to quiet AUTOLOAD
default namarc use_git: 0 (suppress errors in 12_nama.t)
Merge branch 'save-logic'

save foo.json => saves to file foo.json
save foo      => depending on namarc use_git setting:
                 saves to file State.json
                 and makes a commit tagged 'foo'  (use_git: 1)
                 -or-
                 save-to-file 'foo.json'          (use_git: 0)

similar for get_state