DB: Add base files for the DB implem using rust with the diesel crate

src/rust/liblektor-rs/Cargo.toml

src/rust/liblektor-rs/diesel.toml

src/rust/liblektor-rs/migrations/.keep

...tor-rs/migrations/2022-09-30-204512_create_posts/down.sql

...ektor-rs/migrations/2022-09-30-204512_create_posts/up.sql

src/rust/liblektor-rs/src/database.rs

src/rust/liblektor-rs/src/database/mod.rs

src/rust/liblektor-rs/src/schema.rs