Back-trace filtering improvements#8

Merged

eric-martin merged 2 commits intostackify:masterfrom

dimitrytarasov:master

Mar 26, 2015

Commits on Mar 25, 2015

In some cases file and line may be undefined in stack-trace
dimitrytarasov
committed
Do not exclude trace items that do not contain file path
dimitrytarasov
committed