Merge pull request #977 from hpcugent/develop

release EasyBuild v1.14.0
Add download-only basic option to only download
sources and extensions without build software.
Move fetch_extension_source in fetch_step, to allow
use of --stop=fetch to only download sources and
extensions archives.
Add missing check for exts before copying in exts_all.
Add fetch argument to extensions_step for testing purpose.
fix for #980
short-circuit to returning None in det_toolchain_compilers_name_version for dummy toolchain, add FIXME placeholder
Merge branch 'develop' into kcgthb_master
Merge pull request #1 from boegel/imkl_fftw_mpi_fix

reorganize changes in intelfftw.py, also parametrize compiler suffix for fftw wrapper libs
Merge pull request #2 from boegel/imkl_fftw_mpi_fix

fixes for intelfftw.py
Merge pull request #3 from boegel/imkl_fftw_mpi_fix

remove duplicate code in handling of FFTW cdft libs
include clear error message when an MPI library is being installed without a proper toolchain
Merge pull request #990 from boegel/fix_scalapack_inc_imkl

make sure $SCALAPACK_INC_DIR (and $SCALAPACK_LIB_DIR) are defined when using imkl
Merge pull request #987 from hajgato/imkl_fftw_mpi_fix

Intel fftw mpi update for MKL >= 11.1
Merge pull request #992 from boegel/imkl_fftw_mpi_fix

fix error message on missing FFTW wrapper libs
add iimpi toolchain definition
enhance unit test for --list-toolchains
only list toolchain elements once in output of --list-toolchains (fixes #984)
fix remarks
Merge pull request #993 from boegel/iimpi_tc

add iimpi toolchain definition & fix --list--toolchains