Inspect miniz_oxide for antipatters and request Clippy lints

[Shnatsel]

miniz_oxide has undergone a significant safety improvement recently (see #2). It had plenty of avoidable unsafe code. We should look through the changes and request Clippy lints for the antipatterns that were fixed.

The commit range for safety fixes is from Frommi/miniz_oxide@7fc6d66 to Frommi/miniz_oxide@23a6759, both bounds inclusive.

For more info on requesting Clippy lints see #21.

[Shnatsel]

Requested lint for read_unaligned() that's prevalent in the code and can be safely replaced: rust-lang/rust-clippy#4891

There is also a similar write_unaligned() pattern, we'll need to request a lint for it too: Frommi/miniz_oxide@7fc6d66