2.17.0

• Added custom rules to the settings. When a rule's regular expression matches with the url of the problem that is being parsed, the parser configured in that rule is used instead of the default parser.
• Contest parsers now fetch contest problems in parallel, greatly decreasing the time it takes to parse large contests (thanks @mfornet)
• Fixed the Codeforces contest parser for contests which provide problem statements in PDF(s) (thanks @mfornet)
• Fixed the Toph parser so that it also runs on contest problems (thanks @EgorKulikov)