Include multiple arguments for heading, fov, and pitch

[rrwen]

Include multiple arguments for Command Line Interface (CLI) to accept all combinations of heading, fov, and pitch.

For example:

google_streetview --location=46.414382,10.013988;46.414382,10.013988;40.720032,-73.988354 --heading=0;90;180;270 --fov=0;90;120 --pitch -90;0;90

Given 2 locations, 4 headings, 3 fovs, and 3 pitches, the number of images returned from all possible combinations is:

2 x 4 x 3 x 3 = 72 images

The multiple heading parameter is useful for creating panoramic imagery (with rotations from 0 to 270 degrees assuming a fov of 90).

[rrwen]

Now implemented in v1.1.0