Changed shortcut for the embedded terminal emulator

In recent KDE Plasma versions, in a similar way to other desktop environments, the global Ctrl+Alt+T shortcut launches Konsole:

Add a global shortcut (Ctrl+Alt+T) to launch Konsole
https://phabricator.kde.org/D13708

that causes a problem there when a Krusader user presses Ctrl+Alt+T in order to show the embedded terminal emulator. A possible substitute is Ctrl+Alt+E, which is not already taken, and if the user presses Ctrl+Alt+T and sees the problem, he can remember the second letter of "terminal" (or the first letter of "embedded terminal emulator") and press Ctrl+Alt+E.

CHANGED: Shortcut for the embedded terminal emulator

Differential Revision: https://phabricator.kde.org/D23118