Used a less verbose method to parse JSON from responses
Fixed broken encoding of non-latin characters. Fixes #32

The server incorrectly encodes unicode characters in its responses,
causing mojibake when we try to output them.

This may happen with folder names or hostnames, so we need to fix the
encoding on those before continuing.
check_activity now looks for placeholder div. Fixes #24

Previously we checked if the peer's status contained the word "Synced"
to tell if we were syncing or not.  This didn't work if the web
interface was set to a language other than English.  However, looking
for the Up/Down arrow placeholder div will always work.