Implemented ssh command create-group

Often, when creating a new gerrit project a gerrit admin
needs to create a new project owner group and setup an initial
set of group members. This was only possible from gerrit's Web UI
and was a realtively slow process compared to the easiness of
creating the project using the create-project ssh command.

This command makes it possible to create a new group, assign
group members, owner group and description via ssh.

Bug: issue 313
Change-Id: I9fbc013bd5e596f0b23e411ee0cc72d5f67b5f39
Signed-off-by: Sasa Zivkov <sasa.zivkov@sap.com>

gerrit-server/src/main/java/com/google/gerrit/server/account/AccountResolver.java

@@ -46,8 +46,8 @@ public class AccountResolver {
    *
    * @param nameOrEmail a string of the format
    *        "Full Name <email@example>", just the email address
-   *        ("email@example"), a full name ("Full Name"), or an account id
-   *        ("18419").
+   *        ("email@example"), a full name ("Full Name"), an account id
+   *        ("18419") or an user name ("username").
    * @return the single account that matches; null if no account matches or
    *         there are multiple candidates.
    */
@@ -61,7 +61,16 @@ public class AccountResolver {
       return byId.get(Account.Id.parse(nameOrEmail)).getAccount();
     }
 
-    return findByNameOrEmail(nameOrEmail);
+    Account account = findByNameOrEmail(nameOrEmail);
+    if (account != null) {
+      return account;
+    }
+
+    if (nameOrEmail.matches(Account.USER_NAME_PATTERN)) {
+      return findByUserName(nameOrEmail);
+    }
+
+    return null;
   }
 
   /**
@@ -105,4 +114,9 @@ public class AccountResolver {
     final List<Account> r = rs.toList();
     return r.size() == 1 ? r.get(0) : null;
   }
+
+  private Account findByUserName(final String userName) throws OrmException {
+    AccountState as = byId.getByUsername(userName);
+    return as != null ? as.getAccount() : null;
+  }
 }