More updates for first time users.

- Modified sample conf so it is useable by default, also added some
      comments from the 'hello world' configuration.
    - Updated README so there's a clear two step start for newbies.
    - Added extra vim swap files to gitignore.

Change-Id: I76203973db4a7b332014662fcfb2ce5e7d137bd8

.gitignore

@@ -9,8 +9,13 @@
 *.pyc
 *.rej
 *.so
+
+# Editor files #
+################
 *~
 .*.swp
+.*.swo
+
 .DS_Store
 ._*
 .nfs.*

README.md

@@ -39,6 +39,11 @@ For basic help how to get started:
 For first time users, simply run the following:
 
     $ make
+    $ ARGUMENTS="-configFile=documentation/examples/prometheus.conf" make run
+
+``${ARGUMENTS}`` is passed verbatim into the makefile and thusly Prometheus as
+``$(ARGUMENTS)``.  This is useful for quick one-off invocations and smoke
+testing.
 
 If you run into problems, try the following:
 
@@ -56,13 +61,6 @@ staticly link against C dependency libraries, so including the ``lib``
 directory is paramount.  Providing ``LD_LIBRARY_PATH`` or
 ``DYLD_LIBRARY_PATH`` in a scaffolding shell script is advised.
 
-Executing the following target will start up Prometheus for lazy users:
-
-   $ ARGUMENTS="-foo -bar -baz" make run
-
-``${ARGUMENTS}`` is passed verbatim into the makefile and thusly Prometheus as
-``$(ARGUMENTS)``.  This is useful for quick one-off invocations and smoke
-testing.
 
 ### Problems
 If at any point you run into an error with the ``make`` build system in terms of

documentation/examples/prometheus.conf

@@ -1,26 +1,30 @@
+# Global default settings.
 global {
-  scrape_interval: "1s"
-  evaluation_interval: "1s"
-  labels {
-    label {
-      name: "owner"
-      value: "test"
+  scrape_interval: "15s"     # By default, scrape targets every 15 seconds.
+  evaluation_interval: "15s" # By default, evaluate rules every 15 seconds.
+
+  # Attach these extra labels to all timeseries collected by this Prometheus instance.
+  labels: {
+    label: {
+      name: "monitor"
+      value: "codelab-monitor"
     }
   }
-  rule_file: "prometheus.rules"
+
+  # Load and evaluate rules in this file every 'evaluation_interval' seconds. This field may be repeated.
+  #rule_file: "prometheus.rules"
 }
 
-job {
+# A job definition containing exactly one endpoint to scrape: Here it's prometheus itself.
+job: {
+  # The job name is added as a label `job={job-name}` to any timeseries scraped from this job.
   name: "prometheus"
+  # Override the global default and scrape targets from this job every 5 seconds.
   scrape_interval: "5s"
 
-  target_group {
+  # Let's define a group of targets to scrape for this job. In this case, only one.
+  target_group: {
+    # These endpoints are scraped via HTTP.
     target: "http://localhost:9090/metrics.json"
-    labels {
-      label {
-        name: "group"
-        value: "canary"
-      }
-    }
   }
 }