Add an announcement for 6.0

* Change version 

Make the icon font things more clear in NOTICE, include where they are in our source folder. Also move the text at the beginning of the distribution NOTICE file. (#1444)

* Fix #1441 add icon files notice

* Amend notice file, add excluding icon folder in rat config

Sync English documents to Chinese.

* Add Junit test for ribbon's NIWSServerListClassName

* Add License Head to Code file

* try to solve submodule skywalking-ui conflict

Fixed the bug of the result of GC count in query of GC trend service always 0.

* Update How-to-release.md

* Update create_source_release.sh

* Update README.md

* Update README_ZH.md

Error rate alarm is not triggered

* Update submodule skywalking-ui

* Update submodule skywalking-ui

* Update submodule skywalking-ui

* Update submodule skywalking-ui

* #1405
Add application id into service metric for the page jump from overview page to service page.

* Fixed test case error.

* Update submodule skywalking-ui

* Update submodule skywalking-ui

* Update submodule skywalking-ui

* Fixed the wrong usage of elasticsearch filter.

* #1393

The array data type of service name column are nested. Change the data type to be just a one-dimensional array.

* Update submodule skywalking-ui

* Update submodule skywalking-ui

* Prepare beta2 changelogs.

* #1207

Return true when segment parse throw exception to avoid parse the segment over and over again which read from buffer file.

* no message

* #1202

1. Determine the log is enabled for the DEBUG level before printing message.
2. Make the columns initialize to be static attribute.
3. Topology build optimize: Cache query result to avoid repeating queries.

* #1202

Add elasticsearch batch process setting into application.yml.

* #1202

Fixed check style error.

* #1202

Use XContentFactory to build source to insert into elasticsearch.

* support shardingjdbc database storage feature

* dependency and version should be defined in collector root pom.xml

* update the markdown file

* fix errors

* fix checkstyle errors

* add the Logger modifier "static" in pr #1347

* fix the issue #1376

* Remove all license files of Apache 2.0 libs. And add a missing one.

* Restore the Groovy and httpclientcomponent licenses, add a new section in License file for unstandard Apache 2.0 license.

* #1206

1. Support list data type attribute in streaming data.
2. Support multiple service names in segment duration index.

* Fixed the conflict.

* #1206

Add TODO description to notify linjiaqi.

* #1206

Remove @NotNull

* Add login filter

Username and password are stored in application.yml with
prefix "security.user"

* Modify startup script and add webapp.yml config file

* Update quick-start document for default login username/password

* Update deploy document for new webapp.yml config file

* Update license for new files.

* Create Architecture.md

* Update Architecture.md

* Update Architecture.md

* Update Architecture.md

* Update Architecture.md

* Update Architecture.md

* Update README.md

Add link in menu. Also related to #1360

* Update Architecture.md

* Update Architecture.md

* Update Architecture.md

* Update Architecture.md

* Update Architecture.md

* Update Architecture.md

* Add Zipkin receiver

* add the Logger modifier "static" in pr 

* support shardingjdbc database storage feature