Yobi was making public/uploadFiles when it starts, but the directory
looks not to be used.

Yobi did not handle some cases correctly about config files.

* Fix a bug that the config files specified by user are ignored; In the
  case, do not create the files by default even if they don't exist.
* Do not update application.secret if the config file is out of conf
  directory. The file may not be Yobi's.
* Tell the user to update application.secret if Yobi failed to update
  it.
* Refactoring: Move members for config files into the ConfigFile inner
  class

This reverts commit 53920e0.

Copying and creating application.conf from application.conf.default was
done while building but it does not work for standalone distribution
because it does not contain conf directory. The process should be done
at the first starting of Yobi.

Problem: When using a Standalone distribution created by Playframework
2, config files, application.conf and application-logger.xml, in conf
directory are ignored because the distribution has config files in jar
file and use them instead of conf directory.

Solution: Add some lines of shell script into the startup script to set
config files explicitly by "-Dconfig.file" and "-Dlogger.file" so that
Yobi uses them.

The directory doesn't need to be included in standalone distribution
because is already included in jar file.

Remove dependency on application.conf which is created by copying from
application.conf.default.

from pull-request 1509

* refs/heads/feature/mailbox:
  mailbox: Rename notConfiguredKeys to missingKeys
   mailbox: Polish comment of getNotConfiguredKeys
  mailbox: Extract constants from configuration keys
  mailbox: Fix NPE if imap.use is not defined

Reviewed-by: 채수원 

from pull-request 1521

* refs/heads/fix/notification-for-updated-comment:
  notification: Fix emails with same message-id

Reviewed-by: 채수원 

"missingKeys.size() > 0" is better to understand than
"!notConfiguredKeys.isEmpty()".

This refactoring makes:

* finding where a configuration value is used eaiser.
* getting configuration value simple by binding each key with the type
  and the default value.

Note: Unchecked casting is unavoidable because typesafehub/config, the
underlying configuration library for PlayFramework, is not type-safe.

from pull-request 1515

* refs/heads/fix/code-npe-nonexistent-path:
  code: Fix NPE when access nonexistent path

Reviewed-by: 백기선 

from pull-request 1517

* refs/heads/commit-correctGroupOverview:
  corrects sentences about authroizations.

Reviewed-by: 이응준 

from pull-request 1492

* refs/heads/enhance/change-spinner:
  loading-ui: replace spinner ui to progressbar
  lib: add npregress js library

Reviewed-by: 백기선 

from pull-request 1514

* refs/heads/fix/incorrectly-selected-branch:
  code: Do not show selected branch for a commit
  code: Rename getBranchNames() to getRefNames()

Reviewed-by: 백기선 

from pull-request 1510

* refs/heads/docs/we-support-java8:
  State we support Java 8

Reviewed-by: 백기선 

from pull-request 1508

* refs/heads/issue/select-label-color:
  LabelEditor: Fix select color bug when add new label

Reviewed-by: 이응준 

from pull-request 1495

* refs/heads/fix/accept-ko-kr:
  Update backward compatibility notes for 0.8.0
  Fix messages are not shown in preferred language

Reviewed-by: 채수원 

Name    : NProgress
URL     : https://github.com/rstacruz/nprogress
License : MIT

from pull-request 1489

* refs/heads/issue/markdown:
  Markdown: Fix Do not XSS defence

Reviewed-by: 채수원