tweak docs

man/foreman.1

@@ -165,7 +165,7 @@ If a \fB\.foreman\fR file exists in the current directory, default options will
 .
 .nf
 
-concurrency: alpha=0
+concurrency: alpha=0,bravo=1
 port: 15000
 .
 .fi

man/foreman.1.ronn

@@ -132,7 +132,7 @@ If a `.foreman` file exists in the current directory, default options will
 be read from it. This file should be in YAML format with the long option
 name as keys. Example:
 
-    concurrency: alpha=0
+    concurrency: alpha=0,bravo=1
     port: 15000
 
 ## EXAMPLES