Updated entities and converted some long String properties to be stor…

…ed as CLOBs

Upgraded spring and hibernate versions

Migrate to AW API 201806

Merge pull request #287 from dakkad/master

Migrated to AdWords API v201802

Migrate to AW API v201710

Release major version v2.0.0

Add a heading notice on readme.

Merge pull request #237 from googleads/zhuoc-dev

Upgrade to AdWords API v201603

Merge pull request #205 from googleads/zhuoc-dev

Merge from zhuoc-dev: update readme and version

Merge pull request #153 from googleads/v201506_upgrade

Remaining code changes for v201506 upgrade