Updates to mkinit.lua
Updates to mkinit.lua

-- make.path.current_file() returns the makefile of the file we're
currently parsing
-- Using make.message() family of functions to print error messages.
-- Caching of target timestamps (for performance)
-- New "dir_target" target type to represent a directory that needs to
be created
-- New make.util.merge_tables() function to merge tables (in a very
specific way)

ijprest/presto-build,ijprest/presto-build,ijprest/presto-build,ijprest/presto-build