Add 'load directly' mode to default Cucumber test suite (#6664)

Currently `npm test` runs the Cucumber suite with a matrix
configuration for selecting the algorithm (CH, MLD) and data loading
(shared-memory, mmap) options.

However, there is a third data loading option, 'load directly',
which is to directly load the datasets into the osrm-routed process memory.

The code paths for each data loading option are distinct:

Storage::Run + SharedMemoryAllocator
MMapMemoryAllocator
ProcessMemoryAllocator

This commit adds direct data loading as part of the Cucumber
configuration matrix.

This will ensure optional dataset support can be added without any
regressions.

features/support/env.js

@@ -27,7 +27,8 @@ module.exports = function () {
         this.DEFAULT_ENVIRONMENT = process.env;
         this.DEFAULT_PROFILE = 'bicycle';
         this.DEFAULT_INPUT_FORMAT = 'osm';
-        this.DEFAULT_LOAD_METHOD = process.argv[process.argv.indexOf('-m') +1].match('mmap') ? 'mmap' : 'datastore';
+        let loadMethod = process.argv[process.argv.indexOf('-m') +1];
+        this.DEFAULT_LOAD_METHOD = loadMethod.match('mmap') ? 'mmap' : loadMethod.match('directly') ? 'directly' : 'datastore';
         this.DEFAULT_ORIGIN = [1,1];
         this.OSM_USER = 'osrm';
         this.OSM_UID = 1;
@@ -42,7 +43,7 @@ module.exports = function () {
         this.OSRM_IP = process.env.OSRM_IP || '127.0.0.1';
         this.OSRM_CONNECTION_RETRIES = process.env.OSRM_CONNECTION_RETRIES && parseInt(process.env.OSRM_CONNECTION_RETRIES) || 10;
         this.OSRM_CONNECTION_EXP_BACKOFF_COEF = process.env.OSRM_CONNECTION_EXP_BACKOFF_COEF && parseFloat(process.env.OSRM_CONNECTION_EXP_BACKOFF_COEF) || 1.0;
-        
+
         this.HOST = `http://${this.OSRM_IP}:${this.OSRM_PORT}`;
 
         this.OSRM_PROFILE = process.env.OSRM_PROFILE;