The value of \( \int_{-\pi/2}^{\pi/2}\frac{1}{[x]+4}\,dx \), where \( [ \, \cdot \, ] \) denotes the greatest integer function, is:
\( \frac{1}{60}(\pi-7) \)
\( \frac{1}{60}(21\pi-1) \)
\( \frac{7}{60}(\pi-3) \)
\( \frac{7}{60}(3\pi-1) \)