docs: userid for basic auth MUST NOT contain a colon
attachments: Optimize getting list of attachments

Problem: Yobi sent a request to get a list of attachments for each
comments. It issued huge amount of requests when the user read an issue
with many comments.

Solution: Embed the list of attachments as a value of data-attachments
attribute and render the list by using javascript.

I expect the total requests will reduce by 41%.
UserApp: Fix server error caused by OptimisticLockException

OptimisticLockException occurred occasionally when
UserApp.updatePreferredLanguage() is called.
Yobi 0.7.0

Reviewed-by: Suwon Chae <sw.chae@navercorp.com>
Merge branch 'fix/user-lock-exception' of dlab/hive

from pull-request 1376

* refs/heads/fix/user-lock-exception:
  UserApp: Fix server error caused by OptimisticLockException

Reviewed-by: 백기선 <keesun.baik@navercorp.com>
PullRequest: Fix a bug that cannot update pullrequest

Reason: The ref to the merge commit could not be updated because
force-update was false.
Merge branch 'fix/cannot-update-pullrequest' of dlab/hive

from pull-request 1384

* refs/heads/fix/cannot-update-pullrequest:
  PullRequest: Fix a bug that cannot update pullrequest

Reviewed-by: 김덕홍 <insanehong@navercorp.com>
Add the release notes for v0.7.1
Merge branch 'docs/relnotes-0.7.1' of dlab/hive

from pull-request 1385

* refs/heads/docs/relnotes-0.7.1:
  Add the release notes for v0.7.1

Reviewed-by: 김덕홍 <insanehong@navercorp.com>
Yobi 0.7.1

Fix a critical bug that cannot update pullrequests

Reviewed-by: insanehong <insane.hong@navercorp.com>
PullRequest: Fix server error when conflict occurs

Reason: NPE occurred when a merge conflicts because Yobi tries to get
the number of the merged commits even if the list is null.

Solution: Set the list of commits Yobi tries to merge even if the merge
conflicts.
Notification: Use system email address as notification sender

Problem: Many Yobi users had extracted and filtered notification
messages of Yobi from their mailbox by using MUA which supports
groupping by the sender's email address. But if
application.notification.bymail.hideaddress is false, it did not work
because the sender's email address is the user's who causes the
notification.

Solution: Use system email address as the sender's email address of
notification messages even if
application.notification.bymail.hideaddress is false.
Merge branch 'fix/server-error-when-merge-conflicts' of dlab/hive

from pull-request 1386

* refs/heads/fix/server-error-when-merge-conflicts:
  PullRequest: Fix server error when conflict occurs

Reviewed-by: 채수원 <sw.chae@navercorp.com>
Merge branch 'perf/optimize-attachments-listing' of dlab/hive

from pull-request 1373

* refs/heads/perf/optimize-attachments-listing:
  attachments: Optimize getting list of attachments

Reviewed-by: 백기선 <keesun.baik@navercorp.com>
CodeBrowser: Fix a bug that subdirectory is not displayed

Subdirectory was not displayed sometimes because of NullPointerException
which occurs whlie traversing commits of the directory. Yobi tries to
work around the bug JGit traverses history incorrectly but sometimes
even that fails.

Solution: Catch the exception and fall back in slower way.
Merge branch 'docs/userid-must-not-contain-colon' of dlab/hive

from pull-request 1342

* refs/heads/docs/userid-must-not-contain-colon:
  docs: userid for basic auth MUST NOT contain a colon

Reviewed-by: 백기선 <keesun.baik@navercorp.com>
Merge branch 'use-system-email-address-as-notification-sender' of dlab/hive

from pull-request 1387

* refs/heads/use-system-email-address-as-notification-sender:
  Notification: Use system email address as notification sender

Reviewed-by: 백기선 <keesun.baik@navercorp.com>
Sync 'next' with 'master'
Start to develop v0.8.0

Reviewed-by: Suwon Chae <sw.chae@navercorp.com>
IssueView: Turn off issue timeline auto update