add check to see whether binutils is included as build dep when GCCore toolchain is used

intel/2017b toolchain definition (REVIEW)

{lib,tools,vis}[GCCcore/6.4.0] XZ v5.2.3, gettext v0.19.8.1, libxml2 v2.9.4

foss/2017b toolchain definition (REVIEW)

{math}[dummy/] MATLAB v2013b

include Autotools as build dep for netCDF

adding easyconfigs: XZ-5.2.3-GCCcore-6.4.0.eb, gettext-0.19.8.1-GCCcore-6.4.0.eb, libxml2-2.9.4-GCCcore-6.4.0.eb

add peperr extension for R 3.4.0

Linking to ncurses was not done correctly...

sync with develop + fix linking to ncurses in libreadline 7.0 easyconfig using GCCcore/6.4.0

bump version for libyaml, SQLite & Tcl easyconfigs that use GCCcore/6.4.0

remove bare Python easyconfig using GCCcore/6.4.0 toolchain + easyconfigs that require it

bump version for various easyconfigs that use GCCcore/6.4.0

Use `buildopts` instead, see http://www.linuxfromscratch.org/lfs/view/8.0/chapter06/readline.html

bump version for cURL, libsodium and FreeXL easyconfigs that use GCCcore/6.4.0, remove non-dummy Eigen easyconfig (headers only)

Update ncurses to not build a separate libtinfo but provide a soft link instead. Force linking to ncurses in libreadline

{chem}[intel/2017a] NWChem v6.6.revision27746

when using dummy