license extractor

extract dependency license information
add url, email
assert randomization

add randomization to disable assert, 10% chance that test will run with
tests.assertion.disabled=org.elasticsearch
Added note to release script to announce on ML
Fixed test bug, was using value that wasn't generated.
move to [1.0.0] SNAP
[DOCS] made it clearer that the _version is incremented by all write operations (deletes included)
[DOCS] updated json responses after #4310 and #4480

 - Removed "ok": true from response examples
 - Added "created" flag to index response examples
 - Replaced exists flag with found in delete response examples
[DOCS] Tidied up asciidoc for migration page
[SPEC] Added human flag to:
* cluster.node_info
* cluster.node_stats
* indices.segments
* indices.stats
* indices.status
[DOCS] Fixed typo in frontends.asciidoc
[SPEC] Added the routing and timeout params to bulk
[SPEC] Added cat.json
[SPEC] Added cluster.repositories.* and cluster.snapshots.*
[SPEC] Added cluster.stats.json
[SPEC] Added cluster.pending_tasks.json
[SPEC] Added version, version_type to get and get_source
[SPEC] Added _source, _source_include, _source_exclude to get_source
[SPEC] Removed percolate from index.json
[SPEC] Added timeout, master_timeout to cluster.get_settings and cluster.reroute