Move tests on trajectories to Trajectories

Move tests on trajectories to new test file `Trajectories/tests.json`.

Trajectories/tests.json

+[
+    {
+	"title": "Segments",
+	"command":
+	[
+	    "$src_dir/Trajectories/segments.py", "$tests_old_dir/EGr2nd15md4/edgelist.csv",
+	    "segments.graphml"
+	]
+    },
+    {
+	"title": "Cost_functions",
+	"command":
+	[
+	    "$src_dir/Trajectories/cost_function.py", "--graphml",
+	    "$tests_old_dir/Extraction_eddies_region_2_noise/SHPC_anti"
+	],
+	"env": {"PYTHONPATH": "$src_dir/Overlap:$src_dir/Common"},
+	"symlink":
+	[
+	    "$tests_old_dir/EGr2nd15md4/node_id_param.json",
+	    "$tests_old_dir/Segments/segments.graphml"
+	],
+	"exclude_cmp": ["timings.txt"]
+    },
+    {
+	"title": "Greece_segments",
+	"description":
+	"This is a case where the speed is not defined on a whole segment.",
+	"command":
+	[
+	    "$src_dir/Trajectories/segments.py", "$tests_old_dir/Greece_graph/edgelist.csv",
+	    "segments.graphml"
+	]
+    },
+    {
+	"title": "Greece_cost_function",
+	"description":
+	"This is a case where the speed is not defined on a whole segment.",
+	"command":
+	[
+	    "$src_dir/Trajectories/cost_function.py", "--graphml",
+	    "$tests_old_dir/Greece/SHPC_anti"
+	],
+	"env": {"PYTHONPATH": "$src_dir/Overlap:$src_dir/Common"},
+	"symlink":
+	[
+	    "$tests_old_dir/Greece_graph/node_id_param.json",
+	    "$tests_old_dir/Greece_segments/segments.graphml"
+	]
+    },
+    {
+	"title": "Trajectories",
+	"command":
+	[
+	    "$src_dir/Trajectories/trajectories.py",
+	    "$tests_old_dir/Cost_functions/segments_cost_functions.graphml"
+	]
+    },
+    {
+	"title": "Greece_trajectories",
+	"description": "A larger case than Trajectories.",
+	"command":
+	[
+	    "$src_dir/Trajectories/trajectories.py",
+	    "$tests_old_dir/Greece_cost_function/segments_cost_functions.graphml"
+	]
+    }
+]