The Stacks project

Added a new chapter

We moved the later part of the chapter on \'etale cohomology
to a later spot in the Stacks project because this will be needed
in order to make sure there are no forward references later on.

By the way, currently there are 3 forward references which we will
fix soon.

Tags: Added new tags

	Mainly new tags for lemmas/propositions/theorems in the chapter
	on etale cohomology.

Etale Cohomology: More edits

	Coding style...

Etale Cohomology: More edits

	Coding style...

Etale Cohomology: White space changes only

Etale Cohomology: Added it to the project and more edits

	A solution to the problem mentioned in the previous commit may
	be to add parts of the Chapter as Appendices maybe in a smaller
	font. Still not sure.

Etale Cohomology: Lots of edits

	One of the problems is that the coding style is completely
	different and nonuniform. Another is that there is a lot of
	material for which it will not be possible to find proofs
	internally in the stacks project for a long time. Perhaps we
	need to introduce a way of indicating this in the document.

	A better solution is perhaps to add only those parts to the
	actual stacks book published on the web which mesh well with
	the stacks project.

CONTRIBUTORS: Added Min Lee

	See previous commit