Create an Career "Structure" for Training

[MystLeissa]

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This an alternative to my Last Feature Request (I'll link the issue in comments once posted). This would allow Kerbals to train in the career mode without ever launching a vehicle I realize this is SIGNIFICANTLY more involved than my original request so that's why I'm posting it as a separate issue.

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Basically in addition to having the existing part upgrades create a Custom GUI for training Kerbals at the (for example) Science Center/Roster in Career. Similiar to my original request training on this method would be limited to level 1 - 3 until appropriate parts can be created.

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See original issue in comments.

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This is designed to be an ALTERNATIVE to my original issue not an inclusion. If you would be so kind choose one or the other to pursue as both seems like overkill.

[MystLeissa]

#4