Rename 1.12 -> 2.0

Following discussion with Shea and Graham. It's a big enough change
from the last release. Also, from a semver perspective, 2.0 makes more
sense because we did remove some interfaces (like nix-pull/nix-push).

.github/ISSUE_TEMPLATE.md

@@ -14,7 +14,7 @@ Examples of _Nix_ issues:
 
 - Nix segfaults when I run `nix-build -A blahblah`
 - The Nix language needs a new builtin: `builtins.foobar`
-- Regression in the behavior of `nix-env` in Nix 1.12
+- Regression in the behavior of `nix-env` in Nix 2.0
 
 Examples of _nixpkgs_ issues:
 
@@ -24,4 +24,4 @@ Examples of _nixpkgs_ issues:
 
 Chances are if you're a newcomer to the Nix world, you'll probably want the [nixpkgs tracker](https://github.com/NixOS/nixpkgs/issues). It also gets a lot more eyeball traffic so you'll probably get a response a lot more quickly.
 
--->
+-->

doc/manual/release-notes/release-notes.xml

@@ -12,7 +12,7 @@
 </partintro>
 -->
 
-<xi:include href="rl-1.12.xml" />
+<xi:include href="rl-2.0.xml" />
 <xi:include href="rl-1.11.10.xml" />
 <xi:include href="rl-1.11.xml" />
 <xi:include href="rl-1.10.xml" />

doc/manual/release-notes/rl-2.0.xml

@@ -2,9 +2,9 @@
       xmlns:xlink="http://www.w3.org/1999/xlink"
       xmlns:xi="http://www.w3.org/2001/XInclude"
       version="5.0"
-      xml:id="ssec-relnotes-1.12">
+      xml:id="ssec-relnotes-2.0">
 
-<title>Release 1.12 (TBA)</title>
+<title>Release 2.0 (2018-02-??)</title>
 
 <para>This release has the following new features:</para>
 

src/libstore/local-store.hh

@@ -19,7 +19,7 @@ namespace nix {
 /* Nix store and database schema version.  Version 1 (or 0) was Nix <=
    0.7.  Version 2 was Nix 0.8 and 0.9.  Version 3 is Nix 0.10.
    Version 4 is Nix 0.11.  Version 5 is Nix 0.12-0.16.  Version 6 is
-   Nix 1.0.  Version 7 is Nix 1.3. Version 10 is 1.12. */
+   Nix 1.0.  Version 7 is Nix 1.3. Version 10 is 2.0. */
 const int nixSchemaVersion = 10;
 
 

version

@@ -1 +1 @@
-1.12
+2.0