Polish "Add table for supported build tools"

Closes gh-14002

spring-boot-docs/src/main/asciidoc/getting-started.adoc

@@ -40,7 +40,7 @@ By default, Spring Boot {spring-boot-version} requires http://www.java.com[Java
 Spring Framework {spring-version} or above. You can use Spring Boot with Java 6 with some
 additional configuration. See <<howto.adoc#howto-use-java-6>> for more details.
 
-Explicit build support is provided for Maven (3.2+), and Gradle 2 (2.9 or later) and 3.
+Explicit build support is provided for the following build tools:
 
 |===
 |Build Tool |Version
@@ -50,7 +50,6 @@ Explicit build support is provided for Maven (3.2+), and Gradle 2 (2.9 or later)
 
 |Gradle
 |[2.9, 3.x]
-
 |===
 
 TIP: Although you can use Spring Boot with Java 6 or 7, we generally recommend Java 8 if