we've started putting micro-revision.i in the root dir

We used to write src/or/micro-revision.i.

Sometime since git 64676d05 (I think), we started writing just ./micro-revision.i instead.

I guess tor_main.c's "#include "micro-revision.i"" can find it in either place. But it finds the old one in src/or/ even if the newer one gets written to the root dir.