direwolf.desktop: remove xterm hard-coding, fix icon

fixes #308

Per the [desktop entry specification](https://specifications.freedesktop.org/desktop-entry-spec/desktop-entry-spec-latest.html#recognized-keys),
all that should be needed to run direwolf in the default terminal of a
user's system should be setting `Terminal=true`.

Per the [xdg icon theme specification](https://specifications.freedesktop.org/icon-theme-spec/icon-theme-spec-latest.html#icon_lookup),
the `Icon` key in a desktop file should only include the basename of the
icon's filename, not include the extension.

CMakeLists.txt

@@ -31,15 +31,6 @@ set(COPYRIGHT "Copyright (c) 2019 John Langner, WB2OSZ. All rights reserved.")
 add_definitions("-DCOPYRIGHT=\"${COPYRIGHT}\"")
 set(IDENTIFIER "com.${COMPANY}.${APPLICATION_NAME}")
 add_definitions("-DIDENTIFIER=\"${IDENTIFIER}\"")
-# raspberry as only lxterminal not xterm
-if(NOT (WIN32 OR CYGWIN))
-  find_program(BINARY_TERMINAL_BIN lxterminal)
-  if(BINARY_TERMINAL_BIN)
-    set(APPLICATION_DESKTOP_EXEC "${BINARY_TERMINAL_BIN} -e ${CMAKE_PROJECT_NAME}")
-  else()
-    set(APPLICATION_DESKTOP_EXEC "xterm -e ${CMAKE_PROJECT_NAME}")
-  endif()
-endif()
 
 find_package(Git)
 if(GIT_FOUND AND EXISTS "${CMAKE_SOURCE_DIR}/.git/")

cmake/cpack/direwolf.desktop.in

@@ -1,10 +1,10 @@
 [Desktop Entry]
 Name=@APPLICATION_NAME@
 Comment=APRS Soundcard TNC
-Exec=@APPLICATION_DESKTOP_EXEC@
-Icon=@CMAKE_PROJECT_NAME@_icon.png
+Exec=@CMAKE_PROJECT_NAME@
+Icon=@CMAKE_PROJECT_NAME@_icon
 StartupNotify=true
-Terminal=false
+Terminal=true
 Type=Application
 Categories=HamRadio
 Keywords=Ham Radio;APRS;Soundcard TNC;KISS;AGWPE;AX.25