Bump version to 0.6.0 (#90)

Changes included since 0.5.2:

* Add provide/inject methods on component
* Add parent property to component (changes Component.__init__ signature)
* Several other small fixes and improvements

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "collagraph"
-version = "0.5.2"
+version = "0.6.0"
 description = "Reactive user interfaces"
 authors = ["Berend Klein Haneveld <[email protected]>", "Korijn van Golen <[email protected]>"]
 license = "MIT"