bump to 0.5.0

move processing to separate modules
- decanat-engine-case-escape
- decanat-engine-case-for
- decanat-engine-case-if
- decanat-engine-case-else
- decanat-engine-case-close
- decanat-engine-case-variable
- decanat-engine-case-partial

move reporter to a separate module

expose `.render` function