Type safety in Field.setValue() methods [LUCENE-3300]

setValue methods in Field and subclasses should introduce type safety, beacuse what is now possible is to instantiate a BinaryField and set a non-binary value, but introduce it in such way to be able to preserve the ability to yield setValue(string) on parent Field class, e.g.:

```Java
Field b = new BinaryField();
b.setValue( ..byte[] value.. );
```

One idea is to use generics:

```Java
Field s = new StringField();
```

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Migrated from [LUCENE-3300](https://issues.apache.org/jira/browse/LUCENE-3300) by Nikola Tankovic, updated May 09 2016

Start by reading Field and its subclasses, focusing on the setValue methods and the StringField/BinaryField examples in the issue. Determine how type safety can be introduced while preserving setValue(String) through the parent Field class; done means the API design is agreed and invalid value types can no longer be passed to a field.

Written by the indexing model from the issue text.