Automatically set gain, auto-exposure, and gamma to have no effect

[andy-sweet]

Based on a Zulip discussion, we decided that some Spinnaker/GenICam properties do not need to be supported and should automatically set to have no effect.

Based on the GenICam SFNC and the Spinnaker docs, the transformation involving these parameters is

$$Y' = (\text{Gain} (Y + \text{BlackLevel}))^\text{Gamma}$$

Therefore, to have no effect on the output pixel value $Y'$ (other than through $\text{BlackLevel}$), we need the following.

• Gain should be set to 1.
• Gamma should be set to 1.
• Auto-gain should be off.

Similarly, we only allow manual control of exposure (or allow it to be controlled by input triggers), so auto-exposure should also always be off.