The Stacks project

Fix typos

LaTeX: \Sch

	Introduced a new macro

	\def\Sch{\textit{Sch}}

	and replaced all the occurences of \textit{Sch} with \Sch.

LaTeX: \Spec

	Introduced the macro

	\def\Spec{\mathop{\rm Spec}}

	and changed all the occurences of \text{Spec} into \Spec.

Tags: Added new tags

	Also fixed a reference.

Bootstrapping stacks

	We finally proved the analogue for algebraic stacks of the final
	bootstrap theorem for algebraic spaces proved in commit d70ec1d.
	The theorem states that if X ---> Y is a morphism from an
	algebraic space to a stack in groupoids, and if this morphism is
	representable by algebraic spaces, surjective, flat, and locally
	of finite presentation, then Y is an algebraic stack.

	An application (to be added still) is that if G/S is a flat and
	locally finitely presented group scheme, then [X/G] is an
	algebraic stack over S. Etc, etc, etc.

Surjectivity lci locus in Hilbert stack

	Now all the peaces are in place in order to state and prove the
	theorem.