Upgrade to time v0.2 and put it behind a feature flag

This also removes the usage of time in the crate's top-level
documentation example, as was done for the README in #625.

Fix #653.

src/lib.rs

@@ -3,13 +3,11 @@
 //!
 //! ```rust
 //! use rusqlite::{params, Connection, Result};
-//! use time::Timespec;
 //!
 //! #[derive(Debug)]
 //! struct Person {
 //!     id: i32,
 //!     name: String,
-//!     time_created: Timespec,
 //!     data: Option<Vec<u8>>,
 //! }
 //!
@@ -20,7 +18,6 @@
 //!         "CREATE TABLE person (
 //!                   id              INTEGER PRIMARY KEY,
 //!                   name            TEXT NOT NULL,
-//!                   time_created    TEXT NOT NULL,
 //!                   data            BLOB
 //!                   )",
 //!         params![],
@@ -28,22 +25,19 @@
 //!     let me = Person {
 //!         id: 0,
 //!         name: "Steven".to_string(),
-//!         time_created: time::get_time(),
 //!         data: None,
 //!     };
 //!     conn.execute(
-//!         "INSERT INTO person (name, time_created, data)
-//!                   VALUES (?1, ?2, ?3)",
-//!         params![me.name, me.time_created, me.data],
+//!         "INSERT INTO person (name, data) VALUES (?1, ?2)",
+//!         params![me.name, me.data],
 //!     )?;
 //!
-//!     let mut stmt = conn.prepare("SELECT id, name, time_created, data FROM person")?;
+//!     let mut stmt = conn.prepare("SELECT id, name, data FROM person")?;
 //!     let person_iter = stmt.query_map(params![], |row| {
 //!         Ok(Person {
 //!             id: row.get(0)?,
 //!             name: row.get(1)?,
-//!             time_created: row.get(2)?,
-//!             data: row.get(3)?,
+//!             data: row.get(2)?,
 //!         })
 //!     })?;
 //!