Updated Build from Source (markdown)

Build-from-Source.md

@@ -5,38 +5,44 @@ use [Gradle Wrapper](http://vimeo.com/34436402) from the root of the source tree
 The wrapper script serves as a cross-platform, self-contained bootstrap mechanism
 for the build system.
 
-**Before You Start**
+### Before You Start
 
 To build you will need [Git](http://help.github.com/set-up-git-redirect) and
 [JDK 8 update 20 or later](http://www.oracle.com/technetwork/java/javase/downloads).
 Be sure that your `JAVA_HOME` environment variable points to the `jdk1.8.0` folder
 extracted from the JDK download.
 
-**Get the Source Code**
+### Get the Source Code
+
 ```
 git clone git@github.com:spring-projects/spring-framework.git
 cd spring-framework
 ```
 
-**Import Into Your IDE**
+### Build from the Command Line
-
-To import into an IDE, ensure JDK 8 is configured. Then run `./import-into-eclipse.sh` or read
-[import-into-idea.md](https://github.com/spring-projects/spring-framework/blob/master/import-into-idea.md).  
-For IntelliJ please do read the instructions as a straight-up import will not work.
-
-**Run Gradle Tasks**
 
 To compile, test, build all jars, distribution zips, and docs use:
 ```
 ./gradlew build
 ```
 
-To install all spring-\* jars into your local Maven cache:
+The first time you run the build it may take a while to download Gradle and all build dependencies, as well as to run all tests. Once you've bootstrapped a Gradle distribution and downloaded dependencies, those are cached in your $HOME/.gradle directory.
+
+Gradle has good incremental build support so run without `clean` to keep things snappy. You can also use the "-a" flag and the ":project" prefix to avoid evaluating and building other modules. For example, if iterating over changes in `spring-webmvc`, run with the following to evaluate and build only that module:
 ```
-./gradlew install -x javadoc
+./gradlew -a :spring-webmvc:test
 ```
 
-Discover more commands:
+The Gradle daemon eliminates startup overhead. It's enabled by default but sometimes you may need to disable it. For example if building against [JDK 9](https://jdk9.java.net/download/), you may encounter an `Unrecognized VM option` error which halts the build. To avoid that error, add `org.gradle.jvmargs=-XX:MaxMetaspaceSize=1024m -Xmx1024m` to the `gradle.properties` file in your _gradle user home_ directory. See also [GRADLE-3256](https://issues.gradle.org/browse/GRADLE-3256) for details.
+
+To install all Spring Framework jars into your local Maven cache (note that "-x" skips Javadoc generation):
 ```
-./gradlew tasks
+./gradlew install -x javadoc
 ```
+
+### Import Into Your IDE
+
+Ensure JDK 8 is configured properly in the IDE. Then follow the instructions:
+* For Eclipse run `./import-into-eclipse.sh`.
+* For IntelliJ IDEA, a straight-up import will not work. Please read [import-into-idea.md](https://github.com/spring-projects/spring-framework/blob/master/import-into-idea.md).
+