Release 2.1.2-1

This is almost finished now. There are however a few issues that I am still working on.

• d/patches/fix-2.1-build.patch: This needs further research and will change
• d/rules: USE_LIBWRAP should be reenabled
• d/patches/deb-test.patch: The two removed tests need further research
• d/*.symbols: Why were those files mostly empty before?
• deps/picohttpparser: This is most likely a policy violation and needs a separate package.