BUG: Patch float and uint handling in to_numeric
1) Patches `float` handling by reducing the "closeness" level when checking conversions.
2) Patches `uint` handling by allowing casts to `uint` dtypes of equal or lesser size to `int64` (when values are less than `INT64_MAX`

Closes #14941.
Follow-up to #15005.
## [Current coverage](https://codecov.io/gh/pandas-dev/pandas/pull/15024?src=pr) is 84.77% (diff: 100%)
> Merging [#15024](https://codecov.io/gh/pandas-dev/pandas/pull/15024?src=pr) into [master](https://codecov.io/gh/pandas-dev/pandas/branch/master?src=pr) will not change coverage

```diff
@@             master     #15024   diff @@
==========================================
  Files           145        145          
  Lines         51123      51123          
  Methods           0          0          
  Messages          0          0          
  Branches          0          0          
==========================================
  Hits          43337      43337          
  Misses         7786       7786          
  Partials          0          0          
```

> Powered by [Codecov](https://codecov.io?src=pr). Last update [0252385...9e35819](https://codecov.io/gh/pandas-dev/pandas/compare/0252385a71f8b8738c3223dcc44af001baa79b10...9e35819b8efaf6e4f66579f9285c33645ab5ade7?src=pr) thanks!