Qt client: Add mnemonic support to the spy action chooser dialog.

Add mnemonic support to UI name of the action structure and use it in the Qt
client.

See patch #4584

git-svn-id: svn://svn.gna.org/svn/freeciv/trunk@24624 a0f10bec-cc02-0410-94fc-a9cfff90b4cd
Gtk clients: Get the label on a spy action button from its action structure

See patch #4585

git-svn-id: svn://svn.gna.org/svn/freeciv/trunk@24625 a0f10bec-cc02-0410-94fc-a9cfff90b4cd
Make word 2 the UI name of the spy action Industrial Espionage capitalized

so it is consistent with the other spy action UI names.

See patch #4586

git-svn-id: svn://svn.gna.org/svn/freeciv/trunk@24626 a0f10bec-cc02-0410-94fc-a9cfff90b4cd
Copied sdl-client theme as gui-sdl2 theme.

See patch #4568


git-svn-id: svn://svn.gna.org/svn/freeciv/trunk@24627 a0f10bec-cc02-0410-94fc-a9cfff90b4cd
Added modpack type "Musicset"

See patch #4574


git-svn-id: svn://svn.gna.org/svn/freeciv/trunk@24628 a0f10bec-cc02-0410-94fc-a9cfff90b4cd
Put Migrant before Worker in civ2civ3 ruleset so that AI prefers latter.

See patch #4560


git-svn-id: svn://svn.gna.org/svn/freeciv/trunk@24629 a0f10bec-cc02-0410-94fc-a9cfff90b4cd
Send updated information to clients when base or road is added by lua script

See bug #21738


git-svn-id: svn://svn.gna.org/svn/freeciv/trunk@24631 a0f10bec-cc02-0410-94fc-a9cfff90b4cd
Added new files with translatable strings to POTFILES.


git-svn-id: svn://svn.gna.org/svn/freeciv/trunk@24634 a0f10bec-cc02-0410-94fc-a9cfff90b4cd