Update typescript requirement from ^2.7.2 to ^3.0.3 (#420)
Update typescript requirement from ^2.7.2 to ^3.0.3 (#420)

Updates the requirements on [typescript](https://github.com/Microsoft/TypeScript) to permit the latest version.
- [Release notes](https://github.com/Microsoft/TypeScript/releases)
- [Commits](https://github.com/Microsoft/TypeScript/commits/v3.0.3)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
dirigeants/klasa