Revert "Add Project::observeBuffers"

This reverts commit b6fe72ef9e416723f66c775049381c8b28c927f3.

Conflicts:
	src/project.coffee
Revert "Add Project::onDidCreateBuffer"

This reverts commit 4070e5fb25a1c001ee781c28a932c105a5ab1598.
Revert "Add Project::onDidChangePath()"

This reverts commit ed4acb02d8d07eb12b36a7e4d4d5be9db322112b.

Conflicts:
	src/project.coffee