Branch b1_4_mountconf

Branch b1_4_mountconf
b=8007
- put a sem around log writing
- get a mgc ref during process log
- try harder to reactivate a failed-connect mgs import
- be smarter about when we try to copy the mgs logs locally
- make servers always register at startup, so mgs can do some sanity checking
- groundwork for "writeconf"-like regenerate logs