Two graphical overflow bugs in the Group Manager

[snixtho]

Describe the bug
If the list in the members window or "+ Player" window in the group manager have more than 4 entries, it overflows at the bottom.

Expected behavior
Solutions can include having a scrollbar or putting the list into multiple pages. The window itself is definitely too small atm and should resize bigger anyways. But the overflow bug has to be fixed for more entries anyways.

To Reproduce
For the group members window, you need to add 5 or more players. For the "+ Player" window, there must be 5 or more people on the server.

Screenshots/Logs
Group Members:

Add new player:

EvoSC (please complete the following information):

• EvoSC-Version: [e.g. 0.87.x] (get with php esc version)

[itsakt]

Same issue with match settings editor (EvoSC-Version 0.99.23)
Can't edit settings for cup mode.

[snixtho]

Same issue with match settings editor (EvoSC-Version 0.99.23)
Can't edit settings for cup mode.

This is already reported here: #117