Support numeric value in Field class [LUCENE-8870]

I checked the following comment in Field class.

```java
// TODO: allow direct construction of int, long, float, double value too..?
```

We already have some fields like IntPoint and StoredField, but I think it's okay.

The test cases are set in the TestField class.

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Migrated from [LUCENE-8870](https://issues.apache.org/jira/browse/LUCENE-8870) by Namgyu Kim (@danmuzi), updated Jun 26 2019
Attachments: [LUCENE-8870.patch](https://apache.github.io/lucene-jira-archive/attachments/LUCENE-8870/LUCENE-8870.patch)

Start in the Field class by reviewing the TODO about directly constructing int, long, float, and double values, then inspect the existing numeric fields such as IntPoint and StoredField. Use TestField for coverage; done means numeric values can be constructed through Field as intended and the relevant tests pass.

Written by the indexing model from the issue text.