Show long shutter speeds for all selected aperture values

[vodemn]

Describe the feature or the problem it solves Currently the longest shutter speed is 16 seconds which sometimes can limit the exposure pairs list with, for example, f/4 - 16". But there is still some apertures to show.

Describe the solution you'd like

• [x] Implement a formula to generate shutter speeds longer than 1" (https://github.com/vodemn/m3_lightmeter_resources/pull/5)
• [x] Limit equipment profile shutter speed range to 1" (https://github.com/vodemn/m3_lightmeter_iap/pull/10)
• [x] Allow exposure pairs list to grow until the last aperture selected

Additional context Feature request from Google Play review.