Remove support for views

They're replaced by aggregates, which are declarative, faster, and
have a better interface.

src/sql/hydra.sql

@@ -372,57 +372,6 @@ create table SystemTypes (
 );
 
 
--- Views are a mechanism to automatically group related builds
--- together.  A view definition consists of a build of some "primary"
--- job, plus all builds of the other jobs named in ViewJobs that have
--- that build as an input.  If there are multiple builds matching a
--- ViewJob, then we take the oldest successful build, or the oldest
--- unsuccessful build if there is no successful build.
-create table Views (
-    project       text not null,
-    name          text not null,
-
-    description   text,
-
-    -- If true, don't garbage-collect builds included in this view.
-    keep          integer not null default 0,
-
-    primary key   (project, name),
-    foreign key   (project) references Projects(name) on delete cascade on update cascade
-);
-
-
-create table ViewJobs (
-    project       text not null,
-    view_         text not null,
-
-    job           text not null,
-
-    -- A constraint on the job consisting of `name=value' pairs,
-    -- e.g. "system=i686-linux officialRelease=true".  Should really
-    -- be a separate table but I'm lazy.
-    attrs         text not null,
-
-    -- If set, this is the primary job for the view.  There can be
-    -- only one such job per view.
-    isPrimary     integer not null default 0,
-
-    description   text,
-
-    jobset        text not null,
-
-    -- If set, once there is a successful build for every job
-    -- associated with a build of the view's primary job, that set of
-    -- builds is automatically added as a release to the Releases
-    -- table.
-    autoRelease   integer not null default 0,
-
-    primary key   (project, view_, job, attrs),
-    foreign key   (project) references Projects(name) on delete cascade on update cascade,
-    foreign key   (project, view_) references Views(project, name) on delete cascade on update cascade
-);
-
-
 -- A release is a named set of builds.  The ReleaseMembers table lists
 -- the builds that constitute each release.
 create table Releases (