New feature: Multiple filters

One of the features that has been requested repeatedly on our support forum was that of specifying multiple simultaneous filters. We are happy to announce that this is now supported. The "filter" parameter can now specify a comma-separated list of filter. For instance, 

filter=type:article,year:(201.|202.)

will only show journal articles since 2010. Note that this makes use of the fact that filter values are regular expression. So while there is no greater-than filter expression, this expression allows you to specify a range of years.