building: update instructions for AS 3.5

The building from source instructions were written around the time Android Studio (AS) was version 1.5. Since then, some prompts/options have been removed or moved around. Thus, users willing to build from source may get confused with the current instructions. Update the screenshots to show a more version of AS (3.5), and remove the steps that are not longer necessary.

Looks good, thanks @torresariass!

added 1 commit

• b7fb81a0 - building: address review comments by @akwizgran

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Thanks for the review @akwizgran ! I think I addressed both your comments :)

resolved all threads

Thanks @torresariass!

merged

mentioned in commit b4797e90