Insteon: Add Is Deaf Routine for Battery Devices

Closed #279
Insteon: Add is_deaf Check to Sync Links, Fix Dumb Typo

Fix Delete Orphans Logic, had that backwards.
Insteon: Not All References are to Self

Reminder to self: don't use find and replace
Insteon: One More Typo
Fix typo in description of base device's is_deaf default.
Merge pull request #19 from pmatis/fix_issue_279

Fix typo in description of base device's is_deaf default.
Merge pull request #282 from krkeegan/fix_issue_279

Insteon: Add Is Deaf Routine for Battery Devices