setstreamVodField and streamLiveField no longer mutually exclusive

Removed curPage map from IO. bufferFrame now creates this variable locally and passes it to bufferStart, bufferFinalize and bufferNext
Fix keyNum selection with mixed live & VoD data
Fix bufferframe to handle mixed VoD and live
Added check to bufferFrame to not start the countdown timer for removing live pages
Fixed countdown timer being set using keyNum rather than pageNumber, which resulted in the wrong pages being deleted
livePage variable moved from static to private variable to correctly handle multithreaded inputs

# Conflicts:
#	src/io.cpp
#	src/output/output.cpp

src/input/input_buffer.cpp

@@ -317,7 +317,6 @@ namespace Mist{
       break;
     }
 
-    curPageNum.erase(tid);
     INFO_MSG("Should remove track %zu", tid);
     meta.reloadReplacedPagesIfNeeded();
     meta.removeTrack(tid);