Rename doc/manual{src -> source}

This is needed to avoid this
https://github.com/mesonbuild/meson/issues/13774 when we go back to
making our subproject directory `src`.

doc/manual/source/release-notes/rl-1.11.10.md

@@ -0,0 +1,21 @@
+# Release 1.11.10 (2017-06-12)
+
+This release fixes a security bug in Nix’s “build user” build isolation
+mechanism. Previously, Nix builders had the ability to create setuid
+binaries owned by a `nixbld` user. Such a binary could then be used by
+an attacker to assume a `nixbld` identity and interfere with subsequent
+builds running under the same UID.
+
+To prevent this issue, Nix now disallows builders to create setuid and
+setgid binaries. On Linux, this is done using a seccomp BPF filter. Note
+that this imposes a small performance penalty (e.g. 1% when building GNU
+Hello). Using seccomp, we now also prevent the creation of extended
+attributes and POSIX ACLs since these cannot be represented in the NAR
+format and (in the case of POSIX ACLs) allow bypassing regular Nix store
+permissions. On macOS, the restriction is implemented using the existing
+sandbox mechanism, which now uses a minimal “allow all except the
+creation of setuid/setgid binaries” profile when regular sandboxing is
+disabled. On other platforms, the “build user” mechanism is now
+disabled.
+
+Thanks go to Linus Heckemann for discovering and reporting this bug.