[DO NOT REVIEW] [ experiment #8614] using "." for fully qualified names: stdlib.pure.ospaths

[timotheecour]

PR only there for debugging CI issues in #8614

• this variant uses "stdlib.pure.ospaths" instead of "stdlib@pure@ospaths"
• it generates package parents hierachically, exactly as follows:
  module ospaths -> package stdlib.pure (note: fully qualified) => package stdlib

files like these will be generated in nimcache:

stdlib.pure.bitops.c
stdlib.pure.math.c
stdlib.system.c
timn.bugs.exp_module_nonuniq.t01.c

Note

example of things it generates during compilation (with --hint[CC]=on):
CC: stdlib.pure.collections.rtarrays
CC: stdlib.std.sha1
CC: compiler.compiler.prefixmatches
CC: stdlib.pure.concurrency.cpuinfo
CC: stdlib.impure.nre.private.util
CC: stdlib.impure.nre
CC: stdlib.deprecated.pure.asyncio
CC: stdlib.system

depends on:

#8631