build-sys: fix wixl path
wixl: add MSIDefault.actions table with default values
wixl: use MSIDefault.actions in builder sequence_actions()
wixl: add WixLaunchConditions
wixl: simplify default actions insertion
wixl: use default actions values whenever referenced
wixl: some clean-up
wixl: add missing actions and sequences
wixl: move get_attribute_content() to wix.vala
wixl: make methods in util.vala public
tools: add wixl-heat

A tool to generate WiX fragments
wixl: resolve DirectoryRef directory parents
wixl: generate UUID for component Guid=*
wixl: handle ComponentGroup and ComponentGroupRef
wixl: lookup source files using Source attributes if provided
tests: add some wixl-heat tests
wixl: wip
wixl: error out if can't resolve element
wixl: add preprocessor warning and error
wixl: preprocessor learn include