Bugs and updates fixed

PR #10

PR #8

PR #7

Resources path fixed

A better way to reference the path for extra CSS and JS has been implemented to accept a path changed via the host project's composer.json

4.1.0

• add methods to set image and file categories
• add ability to use LinkItem with has_many relation
• fix popup form style
• fix js / css resource path

4.0.2

add update methods for Link() and getMenuItems()

4.0.1

• Add comments

SilverStripe 4 LinkItemField

First release.

• Model
• CMS Field