lzo's download server does not present a valid certificate, so that downloads via https are failing. Spack's MD5 checksum still ensure a safe download.
Closes#1675.
Everything in the __all__ list in the spack module is from some other
module, so only do their documentation in their original location. This
also avoids issues like the fact that some directive names shadow spack
core module names.
@adamjstewart
```
think you'll find that if you try running something like:
spack spec libsplash ^hdf5@1.8.15
It will complain that libsplash does not depend on hdf5.
This is a bug in Spack's dependency resolution. A workaround
for this is to tell it to always depend on hdf5.
```
@davydden
```
to expand on @adamjstewart comment, spack will make a union
of dependencies,
i.e. hdf5@1.8.6: + hdf5+mpi = hdf5:1.8.6:+mpi, that's why it works.
```
thank you for the hint!
Adds a package for
[PNGwriter](https://github.com/pngwriter/pngwriter/),
a simple high-level C++ png API used in scientific projects.
```
PNGwriter is a very easy to use open source graphics library that
uses PNG as its output format. The interface has been designed to be
as simple and intuitive as possible. It supports plotting and reading
pixels in the RGB (red, green, blue), HSV (hue, saturation,
value/brightness) and CMYK (cyan, magenta, yellow, black) colour
spaces, basic shapes, scaling, bilinear interpolation, full TrueType
antialiased and rotated text support, bezier curves, opening existing
PNG images and more.
```
PNGwriter is a dependency for [PIConGPU](http://picongpu.hzdr.de),
an open-source, many-core, fully-relativistic particle-in-cell code
and further software developed at
[Helmholz-Zentrum Dresden - Rossendorf](https://www.hzdr.de).
Adds a package for
[libSplash](https://github.com/ComputationalRadiationPhysics/libSplash),
a high-level library around serial and parallel HDF5 for regular
grids and particle data sets.
```
libSplash aims at developing a HDF5-based I/O library for HPC
simulations. It is created as an easy-to-use frontend for the
standard HDF5 library with support for MPI processes in a cluster
environment. While the standard HDF5 library provides detailed
low-level control, libSplash simplifies tasks commonly found in
large-scale HPC simulations, such as iter- ative computations
and MPI distributed processes.
```
libSplash is a dependency for [PIConGPU](http://picongpu.hzdr.de),
an open-source, many-core, fully-relativistic particle-in-cell
code and further software developed at
[Helmholz-Zentrum Dresden - Rossendorf](https://www.hzdr.de).
libSplash builds in two versions, one without MPI writing
domain-decomposed posix-style HDF5 files per process and one
(default) with MPI and MPI-I/O ("parallel HDF5") support
aggregating into a single file per MPI communicator.
libSplash is used in conjunction with
[openPMD](http://openPMD.org), see also
[github.com/openPMD/](https://github.com/openPMD/).
