Fixes the continue incrementation issue

[Kbz-8]

Fixes issue #86 by adding current loop counter increment right before each continue. Current implementation may be sub-optimal but really simple.

For example, the fix makes this code

[entry(frag)]
fn main()
{
    let value = 1.0;
    for i in 1 -> 5
    {
		if (i == 2)
			continue;
		for j in 1 -> 5
		{
        	if (j == 3)
				continue;
			for k in 1 -> 5
			{
				if (k == 4)
					continue;
				value *= f32(i) + f32(j);
			}
		}
    }
}

generate this GLSL

void main()
{
	float value = 1.0;
	{
		int i = 1;
		int _nzsl_to = 5;
		while (i < _nzsl_to)
		{
			if (i == 2)
			{
				i += 1;
				continue;
			}

			{
				int j = 1;
				int _nzsl_to_2 = 5;
				while (j < _nzsl_to_2)
				{
					if (j == 3)
					{
						j += 1;
						continue;
					}

					{
						int k = 1;
						int _nzsl_to_3 = 5;
						while (k < _nzsl_to_3)
						{
							if (k == 4)
							{
								k += 1;
								continue;
							}

							value *= (float(i)) + (float(j));
							k += 1;
						}

					}

					j += 1;
				}

			}

			i += 1;
		}

	}

}

The fix also works in SPIR-V

[SirLynix]

LGTM, thank you