Add Trace Graph to GUI

Users can view Trace Graph in the GUI
Important things modified:
1: Add a button in the GUI called "Trace Graph", the button will be enabled after users viewing the summary tables.
2: All the trace graph files will be generated behind the scene after users clicking the summary tables.
2: Add a column to "Trace" to the "Fault Injection Status" table. The table currently does nothing. There will be checkboxes implemented later.
3: Fixed a bug when users choose full trace, there were no llfi.stat.trace.xx.txt files generated in llfi_stat_output folder.