The Stacks project

Try to alleviate confusion about Serre subcategories

Not sure this will be helpful, but maybe it is better this way.

Thanks to many people including Mohammed, Bach, Shane, Alejandro
González Nevado.

Fix snafu regarding "Serre subcategories"

	Wasn't careful enough to spell out exactly what was needed to define
	the subcategory of complexes with cohomology in a subcategory. There
	does not seem to be universal agreement on what is a "thick"
	subcategory of an abelian category, so we decided to not use this
	terminology. Instead we used "weak Serre subcategory" to indicate a
	strictly full subcategory closed under kernels and cokernels.

	Let me know if you disagree with this terminology.

LaTeX: \Ob

	Introduced a macro

	\def\Ob{\mathop{\rm Ob}\nolimits}

	and replaced any occurence of \text{Ob}( with \Ob(. There are
	still some occurences of \text{Ob} but these are sets, not the
	operator that takes the set of objects of a category.

New tags added to the project

	modified:   tags/tags

Added Serre subcategories to homology.tex
Lots of edits to intersections.tex

	modified:   homology.tex
	modified:   intersections.tex
	modified:   morphisms.tex
	modified:   my.bib