Update Travis CI and bump CMake

CMakeLists.txt

@@ -1,5 +1,5 @@
 project (uirc3 C)
-cmake_minimum_required (VERSION 2.8.5)
+cmake_minimum_required (VERSION 2.8.11)
 
 # Options
 option (WANT_READLINE "Use GNU Readline for the UI (better)" ON)
@@ -127,12 +127,6 @@ function (make_tests_for target_name)
 	get_target_property (sources   ${target_name} SOURCES)
 	get_target_property (libraries ${target_name} LINK_LIBRARIES)
 
-	# Unfortunately the property is a 2.8.11 feature however we need to
-	# support at least 2.8.7 for now because of Travis CI
-	if (NOT libraries)
-		set (libraries ${project_libraries})
-	endif (NOT libraries)
-
 	set (test test-${target_name})
 	add_executable (${test} ${sources})
 	target_link_libraries (${test} ${libraries})