ARROW-3403: [Website] Source tarball link missing from install page
Author: Krisztián Szűcs <szucs.krisztian@gmail.com>
Closes #2683 from kszucs/ARROW-3403 and squashes the following commits:
6c5fd7ece <Krisztián Szűcs> fix link
diff --git a/install.md b/install.md
index e3ef650..44dddcd 100644
--- a/install.md
+++ b/install.md
@@ -28,7 +28,7 @@
### Source release
-* **Source Release**: [{{site.data.versions['tarball_name']}}][6]
+* **Source Release**: [{{site.data.versions['current'].tarball_name}}][6]
* **Verification**: [asc signature][13], [sha256 checksum][14], [sha512 checksum][15], ([verification instructions][12])
* [Git tag {{site.data.versions['current'].git-tag}}][2]
* [GPG keys for release signatures][11]