This will decrease the risk of running out of file descriptors for the
database and other bad things, which could otherwise potentially happen
if we're serving lots of requests and scanning in parallel, etc.
Windows doesn't have a per process open file limit like Unix so we don't
need to worry about it there.
The number of copiers and pullers is set to default at config loading
time, but the new folder configuration doesn't pass through config
loading so we start up with 0 copiers and 0 pullers and hence get stuck.
I moved the default handling to the puller itself instead. I think this
way is also cleaner as we get to keep the 0 in the config and the puller
gets to decide the defaults on it's own.
* v0.11:
Translations and docs update
Enable browser caching of static resources
Handle multiple case insensitivity prefixes in ignores (fixes#2134)
Make rescan available for unshared folders
Add timeout for peek (fixes#1035)
Fix TestReset when Syncthing shuts down too fast
Clarify password in integration tests
Properly rename config files during integration tests (fixes#1769)
