Squashed commit of the following:

commit 53ba696282e13884d71c54143fdc07a368b26ec1
Author: Jari Oksanen <jari.oksanen@oulu.fi>
Date:   Mon Dec 1 14:10:57 2014 +0200

    Do not import namespace of tcltk

    We need tcltk in one function (orditkplot) and DESCRIPTION only
    suggests the package. However, NAMESPACE has import(tcltk) and if
    tcltk is missing, loading vegan will fail. Now we omit tcltk import
    from the NAMESPACE, and orditkplot uses explicith tcltk:: prefix for
    all ca. 125 tcltk commands so that vegan can be used without tcltk
    package (except for orditlplot)

    I had seen this occasionally in some R builds, but the change was
    triggered by queries from Dave Roberts.

    (cherry picked from commit 2defbae459c0ca0b241dcc48442a4341e6c45564)

commit 099114797874ebb596ab7fb1b6fbebcae4af538c
Author: Gavin Simpson <ucfagls@gmail.com>
Date:   Sat Nov 22 19:40:24 2014 -0600

    use seq_along(x) instead of 1:length(x)

    (cherry picked from commit 2fa9b5d7725bd4dba44741dc607841058e17ff85)

commit 4232fab8f09f6ae37275aef7f9bc5b408953a109
Author: Jari Oksanen <jari.oksanen@oulu.fi>
Date:   Tue Dec 2 18:46:03 2014 +0200

    NEWS on changes in 2.2-1

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/vegan@2914 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Merge branch 'cran-2.2' into r-forge-svn-local

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/vegan@2915 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Update NEWS


git-svn-id: svn://svn.r-forge.r-project.org/svnroot/vegan@2916 edb9625f-4e0d-4859-8d74-9fd3b1da38cb