fix #83 bug with functional keys

[fitiskin]

This problem not only with f5. I'm simply added ignoredKeyCode array with similar.

Timesaving sheet:

Key	Code
pause/break	19
caps lock	20
escape	27
page up	33
page down	34
end	35
home	36
prtscn	44
insert	45
delete	46
left window key	91
right window key	92
f1	112
f2	113
f3	114
f4	115
f5	116
f6	117
f7	118
f8	119
f9	120
f10	121
f11	122
f12	123
num lock	144
scroll lock	145

Also, maybe good idea to add ignoredKeyCode to public options and extend it with existing array.