cards must be removed from filtered decks before they're buried (dae/anki 1df385d)

if not, removeLrn() resets due=odue and odue=0, leading to an invalid
delay calculation when they're later reviewed in the filtered deck

to fix this we'll need to make the same changes required to support
learning cards retaining their state when being emptied from a
filtered deck
Merge pull request #126 from hssm/sched-unbury-filtered

cards must be removed from filtered decks before they're buried (dae/ank...