Upgrade tough-cookie to 0.10.0

Allows more lenient parsing of cookie values.
Merge pull request #763 from stash/stash/tough-cookie-0.10.0

Upgrade tough-cookie to 0.10.0
Fixed auth error for some servers like twisted. According to rfc 2617 auth scheme token should be case-insensitive.
Merge pull request #764 from bobyrizov/master

Case-insensitive authentication scheme