Merge pull request #46 from giselher/variables-fix

Use getitem magic method instead of getattr
remove redundant backslashes
don't die on =breakpoint-created response

A =breakpoint-created response will be sent by gdbs with the feature
"breakpoint-notifications" when the user adds a breakpoint using the CLI.

Note that the response is NOT handled correctly yet -- the parser just does
not die if it is encountered.
don't use logging in parser which runs in a different thread

Logging, in combination with the handlers we're using, will use widgets to
show the errors. Messing with GUI elements from different threads is not
allowed, however; therefore, this would result in a crash.
STL implementation
Added picture
fixed dynamic path
Add svg datagraph routines
Add initial diagram plugin