Added validation to test priority option and updated README and test fixture.

Author: marcelduran

README.md

@@ -125,6 +125,7 @@ _The default WPT server can also be specified via environment variable `WEBPAGET
 * **--tsview** _\<id\>_: test name to use when submitting results to tsviewdb (for private instances that have integrated with tsviewdb)
 * **--tsviewconfigs** _\<string\>_: configs to use when submitting results to tsviewdb (for private instances that have integrated with tsviewdb)
 * **--affinity** _\<string\>_: string to hash test to a specific test agent. tester will be picked by index among available testers
+* **--priority** _\<number\>_: change test priority (0-9) [enforced by API key, otherwise 5]
 * **--noads**: block ads defined by adblockrules.org
 * **--continuous**: capture video continuously (unstable/experimental, may cause tests to fail)
 * **--spdy3**: force SPDY version 3 (Chrome only)
@@ -447,7 +448,9 @@ wpt.runTest(script, function(err, data) {
 * **medianVideo**: _Boolean_, store the video from the median run when capturing video is enabled
 * **htmlBody**: _Boolean_, save the content of only the base HTML response
 * **tsView**: _String_, test name to use when submitting results to tsviewdb (for private instances that have integrated with tsviewdb)
+* **tsViewConfigs**: _String_, configs to use when submitting results to tsviewdb (for private instances that have integrated with tsviewdb)
 * **affinity**: _String_, string to hash test to a specific test agent. tester will be picked by index among available testers
+* **priority**: _Number_, change test priority (0-9) [enforced by API key, otherwise 5]
 * **blockAds**: _Boolean_, block ads defined by adblockrules.org
 * **continuousVideoCapture**: _Boolean_, capture video continuously (unstable/experimental, may cause tests to fail)
 * **forceSpdy3**: _Boolean_, force SPDY version 3 (Chrome only)

lib/mapping.js

@@ -386,8 +386,9 @@ var options = {
     'priority': {
       name: 'priority',
       api: 'priority',
-      param: 'string',
-      info: 'change test priority'
+      param: 'number',
+      info: 'change test priority (0-9) [enforced by API key, otherwise 5]',
+      valid: /^\d$/
     },
     // Undocumented/experimental/transitent/deprecated
     'noads': {

test/fixtures/command-line/help-test.txt

@@ -54,7 +54,7 @@
         --tsview <id>             test name to use when submitting results to tsviewdb (for private instances that have integrated with tsviewdb)
         --tsviewconfigs <string>  configs to use when submitting results to tsviewdb (for private instances that have integrated with tsviewdb)
         --affinity <string>       string to hash test to a specific test agent. tester will be picked by index among available testers
-        --priority <string>       change test priority
+        --priority <number>       change test priority (0-9) [enforced by API key, otherwise 5]
         --noads                   block ads defined by adblockrules.org
         --continuous              capture video continuously (unstable/experimental, may cause tests to fail)
         --spdy3                   force SPDY version 3 (Chrome only)