tracker-miner-fs: Create bus names before touching sensitive files
tracker-miner-fs: Create bus names before touching sensitive files

The miner objects creation (and thus DBus owner requests) have been
moved above in main() to avoid possible race conditions when
checking/removing the no-need-mtime-check file.

It could happen, that if two miner-fs instances are launched
(tracker-control -S sometimes triggers that by activating both
FS/Apps miners, this is an acknowledged race condition in DBus),
one could remove the existing mtime check file, and then fail to
acquire the bus name, leaving the other with a bus name but
ignorant about the mtime check needed.

hoheinzollern/tracker,hoheinzollern/tracker,hoheinzollern/tracker,outofbits/tracker,hoheinzollern/tracker,outofbits/tracker,outofbits/tracker,outofbits/tracker,outofbits/tracker,outofbits/tracker,hoheinzollern/tracker,outofbits/tracker,hoheinzollern/tracker,hoheinzollern/tracker