Added explicit description to hotkeys to remove string table key composing.

git-svn-id: svn://svn.code.sf.net/p/freeorion/code/trunk@7571 dbd5520b-6a0a-0410-a553-f54834df5b05
Patch by vincele: Check if the OIS plugin was created and installed before uninstalling and deleting it.

git-svn-id: svn://svn.code.sf.net/p/freeorion/code/trunk@7572 dbd5520b-6a0a-0410-a553-f54834df5b05