Insteon: Catch Error if Device ID in All_Link_Failure Does Not Exist

Checks to make sure an object exists, if no object exists for that device_id then it sends a message to the log reminding the user to delete_orphan links.

Fixes mstovenour/misterhouse#17
Merge pull request #189 from krkeegan/fix_issue_17

Insteon: Catch Error if Device ID in All_Link_Failure Does Not Exist