[REALASE] aoe_dbsequenzer version 4.0.0

[TASK] Setup Travis Stages  TER Upload
[TASK] Adds tests and change typo3Service injection
[TASK] removes unsupported TYPO3 version in travis tests
[BUGFIX] fixes path to sysext:lang language files in typo3v8
[TASK] updates type definition to doctrine type constants
[CLEANUP] codestyle
[TASK] updates to TYPO3V8 compatibility  doctrine migration
[TASK] updates version & structure in ext_emconf
[TASK] cleanup xclasses
[TASK] updates exception timestamps and removes logic failure with modifyField
[TASK] adds basic v8 compatibility
[CLEANUP] composer dependencies