Add NOMAD_JOB_NAME docs

CHANGELOG.md

@@ -8,6 +8,7 @@ IMPROVEMENTS:
   * client: Enforce shared allocation directory disk usage [GH-1580]
   * client: Introduce a `secrets/` directory to tasks where sensitive data can
     be written [GH-1681]
+  * driver: Export `NOMAD_JOB_NAME` environment variable [GH-1804]
   * driver/docker: Support Docker volumes [GH-1767]
   * driver/docker: Allow Docker logging to be configured [GH-1767]
 

website/source/docs/jobspec/environment.html.md

@@ -52,6 +52,10 @@ environment variables.
     <td>`NOMAD_TASK_NAME`</td>
     <td>The task's name</td>
   </tr>
+  <tr>
+    <td>`NOMAD_JOB_NAME`</td>
+    <td>The job's name</td>
+  </tr>
   <tr>
     <td>`NOMAD_IP_<label>`</td>
     <td>The IP of the the port with the given label</td>
@@ -76,10 +80,11 @@ environment variables.
 
 ## Task Identifiers
 
-Nomad will pass both the allocation ID and name as well as the task's name.
-These are given as `NOMAD_ALLOC_ID`, `NOMAD_ALLOC_NAME`, `NOMAD_ALLOC_INDEX` and
-`NOMAD_TASK_NAME`. The allocation ID and index can be useful when the task being
-run needs a unique identifier or to know its instance count.
+Nomad will pass both the allocation ID and name as well as the task and job's
+names.  These are given as `NOMAD_ALLOC_ID`, `NOMAD_ALLOC_NAME`,
+`NOMAD_ALLOC_INDEX`, `NOMAD_JOB_NAME`, and `NOMAD_TASK_NAME`. The allocation ID
+and index can be useful when the task being run needs a unique identifier or to
+know its instance count.
 
 ## Resources
 

website/source/docs/jobspec/interpreted.html.md

@@ -224,6 +224,10 @@ a particular node and as such can not be used in constraints.
     <td><tt>${NOMAD_TASK_NAME}</tt></td>
     <td>The task's name</td>
   </tr>
+  <tr>
+    <td><tt>${NOMAD_JOB_NAME}</tt></td>
+    <td>The job's name</td>
+  </tr>
   <tr>
     <td><tt>${NOMAD_IP_&lt;label&gt;}</tt></td>
     <td>The IP for the given port <tt>label</tt>. See