Adding support for saveUnknown being an array

# Conflicts:
# lib/Schema.js
# test/Schema.js

Fix loading document type attributes from DynamoDB when when saveUnknown=true

Fix scanByRawFilter containing - Select: 'COUNT'

added support for specifying the ReturnValues option in update

Recreate dynamo db instance on .local()

Update the return type of ddb()

Updated types

Static methods are automatically bound with the context of their Model.

Requiring Node.js version 8.0 and higher

# Conflicts:
# package-lock.json

# Conflicts:
# package-lock.json

Fix saveUnknown throwing errors when value where falsy

Fix `batch*()` methods to accept `KeySchema[]`

This is giving type error when we called the function and when we corrected the type to _AWS.Dyn...

The current solution requires .local() to be called first in order to
use dynamo db locally.

Re...

Adding Node.js version 10 to test matrix

# Conflicts:
# package-lock.json

Project Cleanup

This reverts commit 8eb2765c05f03baa567c04dc5145d644b012fbda.

is unpopulated and therefore by elimination the filter must have contained
```Select='COUNT'```

...

This reverts commit a86b73dc293628744afe274c53f9ef4b9993ba68.

Fixing links in README to changelog and roadmap

# Conflicts:
# docs/_docs/model.md

# Conflicts:
# dynamoose.d.ts
# lib/Table.js
# package-lock.json

Model.getTableReq()

Adding Node.js version 9 to test matrix