update changelog, readme and version

Signed-off-by: Florian Charlier <[email protected]>

update README

Signed-off-by: trevis <[email protected]>

Merge pull request trevismd#29 from trevismd/dev

plot and annotate, use in FacetGrid

Add example to readme

Signed-off-by: Florian Charlier <[email protected]>

Merge pull request trevismd#16 from trevismd/refactoring

Refactoring - Violin plots - And more

Merge pull request trevismd#14 from trevismd/v0.3

update documentation

Update CHANGELOG.md

Update readme.md