Allow aircraft to be selectable from intercept window when out

Feature request 242
Compulsory adoption of new intercept screen
Make LMB consistently set destination in intercept screen
feature242 continued
Fix compile error
  - Remove LanguageState.cpp/.h in openxcom_SOURCES,
    which should be OptionsLanguageState.cpp/.h

Remove whitespaces after backslash complained by Autotools
Merge pull request #664 from keeper7478/master

Fix compile error
Merge branch 'feature242' of https://github.com/cfailde/OpenXcom

Conflicts:
	src/Menu/OptionsAdvancedState.cpp