Revert "inhibit change hooks during (insert content)"

This reverts commit 90d4cae1b1bbfacc612e73444f1e5a723ae4036e.
wait till after content insertion to narrow

Fixes #404 without inhibiting change hooks.
test middle-of-buffer snippet insertion
Merge pull request #412 from npostavs/less-narrow

Wait till after content insertion to narrow