This commit adds a shell script which:
* move current elasticsearch core source in `/core`
* fetch `elasticsearch-parent` project in `/`
* fetch plugins in `/plugins`
* change `groupId` for all plugins to `org.elasticsearch.plugin` so versions won't conflict in maven central
* remove plugins/name/dev-tools dir which is not needed anymore
* remove plugins/name/.git dir
* remove plugins/name/LICENSE and plugins/name/CONTRIBUTING files
* clean `core/pom.xml` of useless settings that are inherited from parent project.
* `core/pom.xml` is adapted to change location of rest tests definition (`../`)
* change core name to `Elasticsearch Core`
* remove `plugins` dir from `.gitignore`
Plugins added:
* Analysis
* analysis-kuromoji
* analysis-smartcn
* analysis-stempel
* analysis-phonetic
* analysis-icu
* Mapper
* mapper-attachments
* Language
* lang-python
* lang-mvel
* lang-javascript
* Cloud
* cloud-gce
* cloud-azure
* cloud-aws
River plugins are ignored but might be added if we want to.
Todo:
* check and adapt our release tool. It now has to upload all submodules as well.
* adapt Jenkins jobs