[release] Bump to version 0.21.0

Put oils-for-unix tarball first on the downloads list.  We've translated
it!

INSTALL.txt

@@ -11,8 +11,8 @@ Quick Start
 
 If you haven't already done so, extract the tarball:
 
-    tar -x --xz < oil-0.20.0.tar.xz
-    cd oil-0.20.0
+    tar -x --xz < oil-0.21.0.tar.xz
+    cd oil-0.21.0
 
 Either install as /usr/local/bin/osh:
 
@@ -33,7 +33,7 @@ The latter doesn't require root access, but it requires:
   (See manpath or $MANPATH.)
 
 NOTE: Out-of-tree builds are NOT currently supported, so you have to be in the
-oil-0.20.0 directory.
+oil-0.21.0 directory.
 
 Smoke Test
 ----------
@@ -52,7 +52,7 @@ More Documentation
 
 Every release has a home page with links, e.g.
 
-    https://oilshell.org/release/0.20.0/
+    https://oilshell.org/release/0.21.0/
 
 System Requirements
 -------------------

build/doc.sh

@@ -540,9 +540,11 @@ tarball-links-row-html() {
 </tr>
 EOF
 
-  # we switched to .gz for oils for Unix
-  for name in oil-$version.tar.{gz,xz} \
+  # we switched to .gz for oils-for-unix
+  # note: legacy names for old releases
+  for name in \
     oils-for-unix-$version.tar.{gz,xz} \
+    oil-$version.tar.{gz,xz} \
     oil-native-$version.tar.xz; do
 
     local url="/download/$name"  # The server URL

devtools/release-note.sh

@@ -15,7 +15,7 @@ source build/dev-shell.sh  # PYTHONPATH
 source devtools/release-version.sh  # for escape-segments
 
 readonly OILS_VERSION=$(head -n 1 oil-version.txt)
-readonly PREV_VERSION='0.19.0'
+readonly PREV_VERSION='0.20.0'
 
 # adapted from release-version.sh
 _git-changelog-body() {

doc/osh.1

@@ -72,7 +72,7 @@ The referenced command or script could not be found.
 .Xr busybox 1 ,
 .Xr sh 1
 .Pp
-.Lk http://www.oilshell.org/release/0.20.0/doc/ Docs
+.Lk http://www.oilshell.org/release/0.21.0/doc/ Docs
 .Sh AUTHORS
 The
 .Nm

doc/release-index.md

@@ -4,7 +4,7 @@ all_docs_url: -
 version_url: -
 ---
 
-Oils 0.20.0
+Oils 0.21.0
 ===========
 
 <!-- NOTE: This file is published to /release/$VERSION/index.html -->
@@ -13,7 +13,7 @@ Oils 0.20.0
 <!-- REPLACE_WITH_DATE -->
 </span>
 
-This is the home page for version 0.20.0 of Oils, a Unix shell.  To use it,
+This is the home page for version 0.21.0 of Oils, a Unix shell.  To use it,
 
 1. Download a source tarball.
 2. Build it and do a "smoke test", as described in [INSTALL][].

doc/release-quality.md

@@ -4,7 +4,7 @@ all_docs_url: -
 version_url: -
 ---
 
-Oils 0.20.0 Quality
+Oils 0.21.0 Quality
 ===================
 
 <!-- NOTE: This file is published to /release/$VERSION/quality.html -->

oil-version.txt

@@ -1,4 +1,4 @@
-0.20.0
+0.21.0
 
 # The first line of this file is the Oil version, and the rest is ignored.
 # It's used at build time for the release tarball, and at runtime for oil