[master] Travis CI + Buildkite 3.0

[kj4ezj]

Change Description

This pull request introduces Travis CI for EOSIO community builds, as well as a new version 3.0 of the Buildkite pipeline for EOSIO organization members.

Changes

• Travis CI YAML
• Buildkite YAML
• Scripts for both in /.cicd
• Generic test scripts in /scripts
• Docker files

Tested

• Buildkite build 16602 — baseline
• Buildkite beta
  • Build 1781 — pinned (base case)
  • Build 1782 — unpinned
    • PINNED='false'
  • Build 1783 — long-running tests
    • SKIP_LONG_RUNNING_TESTS='false'
• Travis CI build 4215

See Also

• Pull request 7815 — eos:release/1.7.x base
• Pull request 7839 — eos:release/1.8.x base
• Pull request 7834 — eos:master base
• Pull request 7700 — eos:develop base
• eos-buildkite-pipelines pull request 54 — pipeline decentralization
• Pull request 7696 — Travis CI beta testing
• Pull request 7622 — Travis CI alpha testing

Consensus Changes

• Consensus Changes
  None.

API Changes

• API Changes
  None.

Documentation Additions

• Documentation Additions
  None.

[kj4ezj]

Remove the submodule changes and the changes to CMakeList.txt caused by the merge from trav-poc to this branch, based off master.