Bump hybrid-array to v0.4

[tarcieri]

@newpavlov not sure what needs to change here:

error[E0432]: unresolved import `cipher::StreamCipherCoreWrapper`
  --> ofb/src/lib.rs:73:5
   |
73 |     StreamCipherCoreWrapper,
   |     ^^^^^^^^^^^^^^^^^^^^^^^
   |     |
   |     no `StreamCipherCoreWrapper` in the root
   |     help: a similar name exists in the module: `StreamCipherCore`

Also looks like the tests need to be updated

[newpavlov]

You need ti enable the stream-wrapper feature on crates which use StreamCipherCoreWrapper.

[tarcieri]

@newpavlov cool, everything compiles now, sans the tests