Merge release-4-5-patches into release-4-6

Merge release-4-5-patches into release-4-6

Avoided the 4.5.6 release patch by using
git merge -s ours 10b109beb3ffa95e37386d38140d2c0fd7769f20
git merge release-4-5-patches
tree=$(git log -1 HEAD --pretty=%T)
git reset --hard $(git cat-file commit HEAD | sed '1,/^$/d' | \
    git commit-tree $tree -p 2b05689 -p 8d6cc14)
Conflict resolution was straightforward, except that the vsite
code was somewhat reorganized in the meantime.

Conflicts:
        Makefile.am
        src/contrib/Makefile.am
        src/contrib/addquote.c
        src/gmxlib/copyrite.c
        src/mdlib/vsite.c

Change-Id: Ib90ac4e55fac308c433b15c344caf5ee41f0146c