If the mempool is not completely full, treat the difference between
the maximum size and the actual usage as available for the coin cache.
This also changes the early flush trigger from (usage > 0.9 * space)
to (usage > 0.9 * space && usage > space - 100MB). This means we're not
permanently leaving 10% of the space unused when the space is large.
749be01 Move GetWarnings() into its own file. (Gregory Maxwell)
e3ba0ef Eliminate data races for strMiscWarning and fLargeWork*Found. (Gregory Maxwell)
c63198f Make QT runawayException call GetWarnings instead of directly access strMiscWarning. (Gregory Maxwell)
dd0df81 Document ConnectBlock connectTrace postconditions (Matt Corallo)
2d6e561 Switch pblock in ProcessNewBlock to a shared_ptr (Matt Corallo)
2736c44 Make the optional pblock in ActivateBestChain a shared_ptr (Matt Corallo)
ae4db44 Create a shared_ptr for the block we're connecting in ActivateBCS (Matt Corallo)
fd9d890 Keep blocks as shared_ptrs, instead of copying txn in ConnectTip (Matt Corallo)
6fdd43b Add struct to track block-connect-time-generated info for callbacks (Matt Corallo)
