Changes

Changes from Mercurial (hg https://foss.heptapod.net/isa-afp/afp-devel/ default)

Changeset 12896:154dc66d9621 by paulson _lp15@cam.ac.uk_: two new lemmas
The file was modified	`thys/Pluennecke_Ruzsa_Inequality/Pluennecke_Ruzsa_Inequality.thy`