Merge in "release-0.6.5"

Merge branch "release-0.6.5" into "develop"

Summary of the merged in commits:
 * 5108f844: Bump version number
 * c1ad5d8b: Add new exercises set for chapter 04
 * 8dea642c: Streamline presentation
 * 4b8aae1f: Streamline presentation
 * ed3da36f: Add more exercises to chapter 01
 * d0a20dfd: Streamline presentation
 * cf0a8acd: Streamline presentation