Make actors outside map borders selectable for their owner

PR #5967 only made planes not lose their selection when they strayed
outside the map border. This PR makes it possible to select them when
they already are outside the map.  It also ensures that the selection
decorations are drawn.  Rank designations, however, will disappear when
a unit leaves the map.

Fixes #5651 for real, then.
Make aircraft not waste their missiles by firing from outside the map

Fixes #6001.

This obviously affects Yaks as well as Migs, even though Yaks had no
trouble with attacking from outside the map.
Merge pull request #5993 from obrakmann/fix5651_take2

More aircraft/shroud interaction fixes
Fix support power selector revealing cloaked enemy units.

Delete unnecessary using line.

Fix spacing.
Merge pull request #6074 from deniz1a/chrono-curtain-select

Fixes #5166
Added BotDebug messages for results of search for a valid support power target location. (+1 squashed commits)

Squashed commits:

[cb3099f] Deleted copy/paste file error. (+1 squashed commits)
[2cd08d2] Renamed PowerBrains to PowerDecisions. (+1 squashed commits)
[9a8ba04] Renamed SupportPowerDecisionBrain to SupportPowerDecision. (+1 squashed commits)
[365aa81] AI Metadata for support powers implemented. Rebased. (+3 squashed commit)
[a4c504f] Fix use of radiusToUse (+3 squashed commit)
[0b2a7c8] Remove unneeded using from SupportPower, was added for phase 1.
[b5d9ba9] Allow decision check radius to be multiplied. (+6 squashed commit)
[7b5482e] Fix to RA misc.yaml
[b4425ae] Fix to D2K structures.yaml
[51b5b4c] Dropped unneeded Self stance that had been added for phase 1.
[e612dc4] Updated RA and D2K yaml.
[0447b9f] Fix AUTHORS.
[3cdfb27] Updated AUTHORS. (+3 squashed commit)
[7c14ce6] Fixed considered attractiveness code. Added debug message if supportpower brain definition missing for an AI. Corrected cost based decision. (+4 squashed commit)
[2e82b99] Moved decisions for supportpowers to HackAI.
[8ab5f22] Phase 2 progress.
[432a1d3] Partial work completed on phase 2 of AI-MetaData. (+1 squashed commits)
[24cfc53] Support Power Metadata. Helps AI understand how a support power is to be used. (+3 squashed commit)
[f9df354] Update .travis.yml
[7abf3ec] Support Power Metadata. Helps AI understand how a support power is to be used.
[77ca5fb] DivideByZero protection. (+1 squashed commits)