* removed header search in subdirectories of header search paths
* cache file node ids in Storage for faster lookup
* retrieve node names from SearchIndex
* fixed addNodeAndAllChildren also called for member edges
* added check if node already present in addEdgeAndAllChildren
This change adds the refresh component that allows for refreshing the source code via UI or shortcut. If automatic
refreshing is activated via the UI, the code is refreshed anytime the window gets focus. The contents of all the
updated source files get removed from Storage, before reparsing them. File dependencies are not respected yet.