Improve performance of FromBytesOrNil (#206)

This pulls code from FromBytes and UnmarshalBinary into FromBytesOrNil
which reduces the cost of creating a UUID from a byte slice. It also
removes an allocation when the UUID is invalid as it no longer generates
an error which is discarded. One downside of this approach is that it
duplicates the logic from UnmarshalBinary.

```
goos: linux
goarch: amd64
pkg: github.com/gofrs/uuid/v5
cpu: AMD Ryzen 9 5950X 16-Core Processor
                        │    old.txt     │            new.txt            │
                        │     sec/op     │    sec/op     vs base         │
FromBytesOrNil/valid-32      3.814n ± 0%    1.118n ± 1%  -70.69% (n=100)
FromBytesOrNil/empty-32   135.3500n ± 0%   0.6514n ± 1%  -99.52% (n=100)
geomean                      22.72n        0.8534n       -96.24%

                        │   old.txt    │                 new.txt                  │
                        │     B/op     │    B/op     vs base                      │
FromBytesOrNil/valid-32   0.000 ± 0%     0.000 ± 0%         ~ (p=1.000 n=100) ¹
FromBytesOrNil/empty-32   96.00 ± 0%      0.00 ± 0%  -100.00% (n=100)

                        │   old.txt    │                 new.txt                  │
                        │  allocs/op   │ allocs/op   vs base                      │
FromBytesOrNil/valid-32   0.000 ± 0%     0.000 ± 0%         ~ (p=1.000 n=100) ¹
FromBytesOrNil/empty-32   2.000 ± 0%     0.000 ± 0%  -100.00% (n=100)
```

Merge pull request #199 from kohenkatz/fixes_195

Proper timestamp calculation for UUID v7

Add "AtTime" generators for V1, V6, and V7 (#142)

* add "AtTime" generators for V1, V6, and V7

* doc: update doc strings

* fix: convenience methods

* test: add tests for AtTime methods

---------

Co-authored-by: Cameron Ackerman <cameron_ackerman@selinc.com>

Implemented support for checkable errors (#131)

add max uuid (#129)

* add max uuid

---------

Co-authored-by: Cameron Ackerman <cameron_ackerman@selinc.com>

Fix TimestampFromV7 error message (#127)

add gomod support (#116)

* add gomod support

* updated readme

* Update go.mod to have minimum go versoin 1.19

---------

Co-authored-by: damareyoh <chackerman@wsu.edu>

Updated V7 generator to Draft04. (#112)

* Updated V7 generator to Draft04.

* comment fixes

* extend test coverage for failing new rand call

* update readme

* fix more comments

Use legacy go versions compatible unix millisecond calculation (#104)

Enhance defaultHWAddrFunc() and tests to hit 100% coverage (#57)

This updates `defaultHWAddrFunc` to use a package-level variable for calling
`net.Interfaces()`, so that we can mock it in unit tests.

Doing so, and writing the related test, allows us to hit 100% coverage.

Signed-off-by: Tim Heckman <t@heckman.io>

Signed-off-by: Tim Heckman <t@heckman.io>
Co-authored-by: Cameron Ackerman <Cameron_Ackerman@selinc.com>