Allow for multiple databases by providing databaseOptions array; add …

[jessrezac]

…notionId to toplevel node

Description

Allows for multiple databases by providing an array composed of objects including id for Notion database id and nodeType for name of node. Also adds notionId as its own node field which is helpful for relating pages across databases since that's what Notion provides.

Motivation and Context

Allows for use of multiple databases, fixes issue #3

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• Security fix (non-breaking change wich fixes a security issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as
  expected)