lib: fix simplify_path for .

Signed-off-by: Jean Privat <jean@pryen.org>
lib: add file::realpath

Signed-off-by: Jean Privat <jean@pryen.org>
niti: add extern `file_realpath`

Signed-off-by: Jean Privat <jean@pryen.org>
tools: move run_global_phases/process_mainmodule into modelbuilder

frontend was to specific

Signed-off-by: Jean Privat <jean@pryen.org>
tools: add test_phase.nit

Signed-off-by: Jean Privat <jean@pryen.org>
lib: add ordered_tree

Signed-off-by: Jean Privat <jean@pryen.org>
model: move MModule related classes into mmodule.nit

Signed-off-by: Jean Privat <jean@pryen.org>
Merge branch 'prepare_projects'