Revert "ensure document.head exists before starting init"

This reverts commit 8bf3608a356b3663c019f5bfb56f82a8cb575fbf.
document.head is not always there at document-start
Release 4chan X v1.8.10.5.
error.toString() can contain path to Greasemonkey script
error.toString() can contain path to Greasemonkey script
Release 4chan X v1.8.10.6.
Merge branch '1.8.10.x' into 1.9.0.x

Conflicts:
	CHANGELOG.md
	LICENSE
	builds/4chan-X-beta.crx
	builds/4chan-X-beta.meta.js
	builds/4chan-X-beta.user.js
	builds/4chan-X-noupdate.crx
	builds/4chan-X-noupdate.user.js
	builds/4chan-X.crx
	builds/4chan-X.meta.js
	builds/4chan-X.user.js
	builds/4chan-X.zip
	builds/updates-beta.xml
	builds/updates.xml
	package.json
Release 4chan X v1.9.0.2.
Merge branch '1.9.0.x'