0.3.0

• Breaking: Raise the minimum supported Rust version to 1.34.2
• Breaking: Rename TokenLock::{read → try_read, write → try_write}, introducing a panicking variation TokenLock::{read, write} of these methods
• Add TokenLock::{get, try_get, replace, replace_with, try_replace_with, clone, try_clone, swap, try_swap, take, try_take}
• Implement Default