Group admins or members are listed on issue's Assignee list.

Cause:
There is VOC.
When writing an issue on a protected project, we need to assign the issue to someone who is group member. But assignee list includes only project members.

Solution:
This already has been solved. 1ba9698
But there is a bug that Group admins are not listed on private project which has a group.
So group admins are added to assignee list on private project's issue.

Private-issue: 1297
Project: minor layout improvement of dashboard
Merge branch 'issue-1554' of dlab/hive

from pull request 1113
Milestone : Add search feature in milestone detail view
Global: fixed a bug invalid process time in default action
Merge branch 'bugfix/issue-1559' of dlab/hive

from pull request 1118
Fix missing object exception during outdated detecting

Problem: While checking whether a comment thread is outdated,
MissingObjectException might occur if the thread is on a missing git
object.

Solution:
* Consider such kind of thread as outdated one to avoid the exception.
* Log a warning message.
Project: "no assignee" avatar on dashboard
git: Fix possible omission of object while pushing

Yobi still used alternate object database when advertising.
Comment: confirm before exit page if form is not empty
Change expressions in korean of unload confirm
readme: change url caused by transferring yobi repository

  Github yobi repository's ownership is changed, nforge to naver.
  Now, yobi official github repository url is 'https://github.com/naver/yobi'.
  So, changed url of readme and feedback link.
Merge branch 'enhancement/issue-1572-confirm-beforeunload-for-commentform-master' of dlab/hive

from pull request 1130
Attachment: Allow HTTP cache

Set Cache-Control header to "private, no-store, max-age=3600".

I chose the directives based on following reasons:

* "private" avoids that attachments whose access is restricted are
  shared publicly.
* "no-store" reduces possibility that sensitive attachments are leaked
  to a person who has no permission. e.g. A member of private project
  might sell his laptop. The member believed sensitive files are deleted
  by self completely but the web browser's cache may still have
  sensitive attachments.
* See warning below for "max-age=3600".

Warning: This patch introduces a side-effect that a user still access
attachments, from the user's private cache, which the user "had" the
permission but not now. "max-age=3600" directive helps to relieve the
problem by telling the cache to expire the attachment which is older
than 3600 seconds.
No confirm on unload which triggered by submitting form
Merge branch 'fix/issue-1623-annoyingconfirm-onsubmit-comment' of dlab/hive

from pull request 1140
readme: make readme better

  - add detailed descriptions
  - add descriptions for those who don't have git client tools
  - remove unnessary words & sentences
  - add upgrade, backup guide
Adds `80.sql` to delete rows including notification types which are not exist.

Cause:
`PULL_REQUEST_REVIEWED` and `PULL_REQUEST_UNREVIEWED` is united to `PULL_REQUEST_REVIEW_STATE_CHANGED` on 59594601dfde26c5172b862c406d28acdb3f643e.
But rows getting these event types are not removed on `user_project_notification` table.

Solution:
On Ups, these are removed and `PULL_REQUEST_REVIEW_STATE_CHANGED` is added with `TRUE` for `allowed` column.
On Downs, all rows which contain `PULL_REQUEST_REVIEW_STATE_CHANGED` will be removed. And rows with `PULL_REQUEST_REVIEWED` and `PULL_REQUEST_UNREVIEWED` are added and set to `TRUE` for `allowed` column.

Private-issue: 1586
Merge branch 'master-issue-1586' of dlab/hive

from pull request 1135
Merge branch 'fix/git-alternates' of dlab/hive

from pull request 1128