Release 4.5.6

- Updated the version to 4.5.6 in CMakeLists.txt, configure.ac
  and gromacs.7
- Regenerated man-pages and completions

Change-Id: I7692220dfe20248b4cdbdd1ed242d1d97f56fda5
Add fftpack to EXTRA_DIST

The new fftpack files added by 51c2f6c are only compiled if
fftpack is used. Thus "make dist" does not included those
by default.

Change-Id: Id51bba3c622a7087f35e74f7c499b066f095fd0d
fix invalid read in construct_vsites

* aj is not available in the F_VSITEN case hence cannot be read in
  the common part of the function

Change-Id: Ic98dfb91eb095aea933abc3dbfb4f5cc10bf4166
Plain text quotes.

And removed 5 gurgles and 2 bromacses - replaced the bromacses
by new and exciting ones.
Change-Id: Ibdad70d6ceb0caa52be351762704a677e9dddba8
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