Fixes for build system (notably the version number)

[StefansM]

Fixes the issue with git describe described in the review of #22. It's still a mystery to me how I built the 1.0.0 tarball.

Also fixes *_LDFLAGS in Makefile.am: I was passing WARN_CFLAGS rather than WARN_LDFLAGS.

[livibetter]

@StefansM

I'm confused by

GitHub uses lightweight tags to describe releases (for some reason), [...]

Did you mean: Git uses annotated tags to git-describe by default, if without --tags?

If you did mean GitHub, I've just created a test repository, GitHub does recognize both lightweight and annotated tags as releases. I tagged 3, 2 annotated and 1 lightweight. GitHub showed 3 releases and 3 tags. And the annotated tags' messages were also used in Releases (formatted in pre-like block just as commit message)

Anyway, I think annotated tags are better, because I wasn't entirely happy with only putting release notes in GitHub Release as it's not portable (or not with repository in other words), with annotated tags, that will be resolved. Furthermore, git-tag(1) is telling me that I've been using lightweight tags wrong:

Annotated tags are meant for release while lightweight tags are meant for private or temporary object labels. For this reason, some git commands for naming objects (like git describe) will ignore lightweight tags by default.

I am going to add the use of it in release process of pipes.sh, and stop using lightweight tags as release tags.

[StefansM]

GitHub uses lightweight tags to describe releases (for some reason), [...]

Did you mean: Git uses annotated tags to git-describe by default, if without --tags?

Both: if I create a release using the GitHub web UI, GitHub creates a lightweight tag. The git describe command, by default, only looks for annotated tags, so it doesn't see tags made by GitHub unless --tags is given.

Anyway, I think annotated tags are better [for releases]

Definitely agreed. This seems so clear that I just assumed GitHub was creating an annotated tag for a release. It didn't even occur to me that it would (mis)use lightweight tags to do so!

I am going to add the use of it in release process of pipes.sh, and stop using lightweight tags as release tags.

I will do the same. In fact, I think I must have created an annotated tag on my local fork to build the 1.0.0 tarball, and then deleted it in favour of using the web UI. I won't rewrite history in the repo, but all future releases will be annotated. I will bump the version number to 1.0.1 for this PR.