added userFormat,

[tacruc]

So the app is now able to read in Version's from Snapshots of user directory's for example:

data/user1
data/user2

with snapshot

/snapshots/user1.20170505
/snapshots/user1.20170504
/snapshots/user2.20170505
/snapshots/user2.20170504

can be configured with:

snapshotFormat /snapshots/%snapshots%/
dateFormat *Ymd
userFormat \w+\d+