- add flags to find_file_open():
- FF_PATH: enumerate path argument
- FF_NODIR: only match regular files
- FF_NOXXDIR: do not match . or ..
- FF_ONLYDIR: do not match non directories
- 0..15: max recursion depth
- add recursion level in find_file_next()
- add completion pointer in CompleteState
- add CF_DIRNAME and CF_RESOURCE CompletionDef flags
- pass filename to load_ligatures() and load_input_methods()
- remove find_resource_file() dummy definition in html2png.c
- add dir and resource completion methods
- allow makepath() to modify path in place
- enable completion in `load-resource-file` and `load-file-from-path`
- move language syntax handling to `lang` directory
- move other modes to `modes` directory
- move tools to `tools` directory
- compile tools to `bin` directory
- bump version to 5.3alpha
- remove duplicate node names in qe-doc
- update Makefiles
