Just use temp buffer for tar output
Add Robe::Visor#resolve_path
Simplify Robe::Visor#resolve_context
Update ScopedVisor
Robe::Visor#resolve_context: prioritize deeper nesting
Sash#complete_const: Complete nested constants implicitly
#complete_const: complete the constants in all containing scopes
robe-complete-thing: pass the context to #complete_const