Add "Clone As" to repositories and generate full clone commands in UI

Summary:
Ref T4175.

  - Add a configurable name for the clone-as directory, so you can have "Bits & Pieces" clone as "bits~n~pieces/" or simliar.
  - By default, use "reasonable" heruistics to choose such a name.
  - Generate a copy/pasteable clone commmand with this directory name.

Test Plan: Looked at some repositories.

Reviewers: btrahan, chad

Reviewed By: chad

CC: aran

Maniphest Tasks: T4175

Differential Revision: https://secure.phabricator.com/D8097

src/applications/diffusion/controller/DiffusionRepositoryEditBasicController.php

@@ -28,6 +28,7 @@ final class DiffusionRepositoryEditBasicController
 
     $v_name = $repository->getName();
     $v_desc = $repository->getDetail('description');
+    $v_clone_name = $repository->getDetail('clone-name');
     $e_name = true;
     $errors = array();
 
@@ -35,6 +36,7 @@ final class DiffusionRepositoryEditBasicController
       $v_name = $request->getStr('name');
       $v_desc = $request->getStr('description');
       $v_projects = $request->getArr('projectPHIDs');
+      $v_clone_name = $request->getStr('cloneName');
 
       if (!strlen($v_name)) {
         $e_name = pht('Required');
@@ -50,6 +52,7 @@ final class DiffusionRepositoryEditBasicController
         $type_name = PhabricatorRepositoryTransaction::TYPE_NAME;
         $type_desc = PhabricatorRepositoryTransaction::TYPE_DESCRIPTION;
         $type_edge = PhabricatorTransactions::TYPE_EDGE;
+        $type_clone_name = PhabricatorRepositoryTransaction::TYPE_CLONE_NAME;
 
         $xactions[] = id(clone $template)
           ->setTransactionType($type_name)
@@ -59,6 +62,10 @@ final class DiffusionRepositoryEditBasicController
           ->setTransactionType($type_desc)
           ->setNewValue($v_desc);
 
+        $xactions[] = id(clone $template)
+          ->setTransactionType($type_clone_name)
+          ->setNewValue($v_clone_name);
+
         $xactions[] = id(clone $template)
           ->setTransactionType($type_edge)
           ->setMetadataValue(
@@ -93,6 +100,15 @@ final class DiffusionRepositoryEditBasicController
           ->setLabel(pht('Name'))
           ->setValue($v_name)
           ->setError($e_name))
+      ->appendChild(
+        id(new AphrontFormTextControl())
+          ->setName('cloneName')
+          ->setLabel(pht('Clone/Checkout As'))
+          ->setValue($v_clone_name)
+          ->setCaption(
+            pht(
+              'Optional directory name to use when cloning or checking out '.
+              'this repository.')))
       ->appendChild(
         id(new PhabricatorRemarkupControl())
           ->setName('description')