Fix some clippy warnings

[EverlastingBugstopper]

This PR removes the following clippy warnings:

warning: You checked before that `unwrap()` cannot fail. Instead of checking and unwrapping, it's better to use `if let` or `match`.
  --> src/commands/kv/bulk/delete.rs:44:20
   |
41 |             if keys_vec.is_err() {
   |                ----------------- the check is happening here
...
44 |                 Ok(keys_vec.unwrap())
   |                    ^^^^^^^^^^^^^^^^^
   |
   = note: `#[warn(clippy::unnecessary_unwrap)]` on by default
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_unwrap

warning: You checked before that `unwrap()` cannot fail. Instead of checking and unwrapping, it's better to use `if let` or `match`.
  --> src/commands/kv/bulk/put.rs:33:51
   |
30 |             if data_vec.is_err() {
   |                ----------------- the check is happening here
...
33 |                 let data_vec: Vec<KeyValuePair> = data_vec.unwrap();
   |                                                   ^^^^^^^^^^^^^^^^^
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_unwrap

warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
  --> src/commands/kv/bulk/put.rs:65:12
   |
65 |     pairs: &Vec<KeyValuePair>,
   |            ^^^^^^^^^^^^^^^^^^ help: change this to: `&[KeyValuePair]`
   |
   = note: `#[warn(clippy::ptr_arg)]` on by default
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg

warning: this function has too many arguments (8/7)
  --> src/commands/kv/key/put.rs:17:1
   |
17 | / pub fn put(
18 | |     target: &Target,
19 | |     user: &GlobalUser,
20 | |     id: &str,
...  |
25 | |     expiration_ttl: Option<&str>,
26 | | ) -> Result<(), failure::Error> {
   | |_______________________________^
   |
   = note: `#[warn(clippy::too_many_arguments)]` on by default
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#too_many_arguments