Allow slashes in filter regular expressions

Match each tag separately against user filter regular expression

Each article's tag should be matched against user filter regular
expression separately. Current matching confuses when you want to match
an exact tag. You suppose to write "^tag$", bug now have to write
"(^|,)tag(,|$)" which is very inconvenient and requires knowledge about
how do you process this matching.

User's regular expressions need escaping before passing them to
preg_match()

increase updstart locking interval to prevent concurrent updates; decrease batch size for the daemon

increase default batch size
remove random check between feedbrowser or update task executing

sort chronologically instead of random