Item list incomplete when linking to existing items from channel

[J-N-K]

The problem

When linking a channel from the things/channels page to an existing item only some items are displayed. E.g when linking a Number channel, only Number items are displayed. The is wrong because if you want to link the channel using the system range profile, the target item needs to be a Switch. This is also inconsistent because when linking to a new item you can select the item type and use the profile.

Expected behavior

Linking to existing items using profiles works for all items.

Steps to reproduce

1. Install Astro Binding
2. Create a Switch item
3. Try to link the existing item to the rise#duration channel using the system:range profile