Clarify the use of spring.profiles

Fixes gh-1470

Author: snicoll

spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc

@@ -32,7 +32,7 @@ content into your application; rather pick only the properties that you need.
 	spring.config.location= # location of config file
 
 	# PROFILES
-	spring.profiles= # comma list of active profiles
+	spring.profiles.active= # comma list of <<howto-set-active-spring-profiles,active profiles>>
 
 	# APPLICATION SETTINGS ({sc-spring-boot}/SpringApplication.{sc-ext}[SpringApplication])
 	spring.main.sources=

spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc

@@ -453,6 +453,9 @@ by using a `spring.profiles` key to indicate when the document applies. For exam
 		address: 192.168.1.120
 ----
 
+In the example above, the `server.address` property will be `127.0.0.1` if the `development`
+profile is active. If the `development` and `production` profiles are **not** enabled, then the
+value for the property will be `192.168.1.100`
 
 
 [[boot-features-external-config-yaml-shortcomings]]
@@ -638,6 +641,9 @@ For example, when an application with following properties is run using the swit
 	spring.profiles.include: proddb,prodmq
 ----
 
+NOTE: Remember that the `spring.profiles` property can be defined in a YAML document
+to determine when this particular document is included in the configuration. See
+<<howto-change-configuration-depending-on-the-environment>> for more details.
 
 
 [[boot-features-programmatically-setting-profiles]]