Bump stdlib version to 0.1.0

[awvwgk]

Create first release for stdlib. The release notes will be build from the current changelogs entries, feel free to suggests additions to the changelog. After this patch is merged, a new release will be tagged with v0.1.0.

Features, proposals, and fixes that should be included in the first release of the Fortran standard library (0.1.0) should be added to the milestone v0.1.0.

Closes #292
Requires #537

[jvdp1]

Nothing special. I agree with it.

[awvwgk]

There is now a release draft (visible to all maintainers) at https://github.com/fortran-lang/stdlib/releases, you can edit the draft and save the changes there with the save draft button (note that release drafts don't have a permanent URL, therefore I can't link it from here).

[jvdp1]

Thank you @awvwgk for this work.

while I was checking the links for #272, I was wondering if this version number should also appear in stdlib.fortran-lang.org. CHANGELOG.md might be already consider by ford. However I didn't check it. Probably good to check this at the end of this PR.

[zoziha]

@awvwgk Linspace, logspace, and arange should belong to stdlib_math. (I tried to modify the draft.)
Thanks, this PR is really a milestone.
Maybe someday we can install fortran stdlib on msys2 :)

[awvwgk]

Maybe someday we can install fortran stdlib on msys2 :)

I can setup a PKGBUILD once this is merged. Packaging for msys2 is quite straight-forward, you can try it yourself by adjusting fpm-git PKGBUILD given in https://github.com/fortran-lang/fpm/wiki/Packaging-Fpm#msys2-windows for CMake.

[Jim-215-Fisher]

Finally, we have a release version. Regarding to stdlib_stats_distribution_PRNG module, I am not sure whether it should be in stats_distribution package. GSL has a separate random numbers package in addition to random distributions and statistics.

[awvwgk]

@Jim-215-Fisher I opened #544 to discuss the potential change regarding the PRNG distribution module.

[awvwgk]

I'll go ahead and merge this PR and publish the first release of stdlib. Thanks everybody for the hard work so far.

[jvdp1]

Thank you @awvwgk for all your work to make this first release!