Bug fixes

Bug fixes in sulley/primitives.py, sulley/sessions.py, web/templates/index.html, .
1) primitives.py: enhancements in Byte, Word, DWord and QWord classes not to copy-paste loads of  args led to misplacement of args + two other minor bugs
2) sessions.py: in functions Session.fuzz and Session.num_mutations path parameter's default value as () led to append operation on immutable tuples
3) index.html: omitted quotes in line 1