rewrite to use json for storage instead of sqlite. e4af001 updated readme bb327d3 extensive rewrite to use json for storage: e4856f6 more testing 3578c80 bumped version in Cargo.toml 87bf08a expanded testing 967ac7e travis using single-threaded testing ec59c5f make test is now single-threaded 2cb85a4 testing create/delete 8d0f0b4 clarified upgrade process and note section