Correct descriptions

Segments is no longer a test with only isolated segments since commit
e1c18ad8.

Trajectories/Tests/tests.json

@@ -35,8 +35,7 @@
             "$tests_old_dir/EGr2nd15md4/edgelist.csv",
             "segments.graphml"
 	],
-	"sel_diff_args": {"exclude": ["timings_segments.txt"]},
-	"description": "This is a case with only isolated segments."
+	"sel_diff_args": {"exclude": ["timings_segments.txt"]}
     },
     "Cost_functions": {
 	"command": [
@@ -46,8 +45,7 @@
             "$tests_old_dir/Segments/segments.graphml",
             "segments_cost_functions.graphml", "--debug"
 	],
-	"sel_diff_args": {"exclude": ["timings.txt"]},
-	"description": "This is a case with only isolated segments."
+	"sel_diff_args": {"exclude": ["timings.txt"]}
     },
     "Greece_segments": {
 	"description": "This is a case where the speed is not defined on a whole segment.",
@@ -84,8 +82,7 @@
 	"command": [
             "$src_dir/Trajectories/trajectories.py",
             "$tests_old_dir/Cost_functions/segments_cost_functions.graphml"
-	],
-	"description": "This is a case with only isolated segments."
+	]
     },
     "Greece_trajectories": {
 	"description": "A larger case than Trajectories.",