Allow float comparison with zero

[konstin]

cargo clippy -V: clippy 0.0.212 (d61b254 2019-02-19)

Clippy should allow float comparison with zero. The current behavior seems to be a regression as this has apparently already been reported and fixed in #165/#1142.

error: strict comparison of f32 or f64
   --> tests/test_datetime.rs:125:5
    |
125 |     assert_eq!(offset, 0f32);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: #[deny(clippy::float_cmp)] on by default
note: std::f32::EPSILON and std::f64::EPSILON are available.
   --> tests/test_datetime.rs:125:5
    |
125 |     assert_eq!(offset, 0f32);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#float_cmp
    = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)

[oli-obk]

This might not even be a regression, but just a problem with assert_eq. Our const folder does not know about references, so &offset == &0 will still get linted about.