Issue 84 heap parsing in separate thread 1

fixes #84 

not huge improvements:

- parsing of heap dump happens in a different thread
- added helpers to convert msgpack objects into qt specific classes
- added an event parser which parses event collection
- iterating through object dump is fast, but converting objects to ObjectDetail is still slow.
  + maybe we should not convert to msgpack::object to objectDetail, and persist objects directly to db.
for first question, ie copying of data using signals and slots, i dumped underlying data pointers for, and here is what i've got:

```
i tid:0x11d924000 processEvent():206 dump ptr: 0x11dec7000
i tid:0x11d8a1000 dump():24 dump ptr: 0x11dec7000
```
so, in both the threads, data pointer is same. so, i guess there is no copying happening.