CrashSender fails distiguishing same named files in different paths

[a For]

m_FileItems is mapped by filename instead of full file path causing it to drop files with the same name even if they come from different paths.  This is particularly bad for the wildcard option where this usage is very common eg. AddFile("*.log"); AddFile("otherFolder\*.log")

Fix is to use m_sSrcName in every usage of mFileItems instead.