Mention external deps in installation instructions

Fixes #1143

docs/installation.md

@@ -127,6 +127,8 @@ Download the following artifacts from maven:
 
 *   [error_prone_core-2.3.2-with-dependencies.jar](https://repo1.maven.org/maven2/com/google/errorprone/error_prone_core/2.3.2/error_prone_core-2.3.2-with-dependencies.jar)
 *   [jFormatString-3.0.0.jar](https://repo1.maven.org/maven2/com/google/code/findbugs/jFormatString/3.0.0/jFormatString-3.0.0.jar)
+*   [dataflow-2.5.7.jar](https://repo1.maven.org/maven2/org/checkerframework/dataflow/2.5.7/dataflow-2.5.7.jar)
+*   [javacutil-2.5.7.jar](https://repo1.maven.org/maven2/org/checkerframework/javacutil/2.5.7/javacutil-2.5.7.jar)
 *   [javac-9+181-r4173-1.jar](https://repo1.maven.org/maven2/com/google/errorprone/javac/9+181-r4173-1/javac-9+181-r4173-1.jar)
 
 and add the following javac task to your project's `build.xml` file:
@@ -142,6 +144,8 @@ and add the following javac task to your project's `build.xml` file:
     <path id="processorpath.ref">
       <pathelement location="${user.home}/.m2/repository/com/google/errorprone/error_prone_core/2.3.3-SNAPSHOT/error_prone_core-2.3.3-SNAPSHOT-with-dependencies.jar"/>
       <pathelement location="${user.home}/.m2/repository/com/google/code/findbugs/jFormatString/3.0.0/jFormatString-3.0.0.jar"/>
+      <pathelement location="${user.home}/.m2/repository/org/checkerframework/dataflow/2.5.7/dataflow-2.5.7.jar"/>
+      <pathelement location="${user.home}/.m2/repository/org/checkerframework/javacutil/2.5.7/javacutil-2.5.7.jar"/>
       <!-- Add annotation processors and Error Prone custom checks here if needed -->
     </path>
 
@@ -209,9 +213,12 @@ Example:
 
 ```bash
 wget https://repo1.maven.org/maven2/com/google/errorprone/error_prone_core/2.3.2/error_prone_core-2.3.2-with-dependencies.jar
+wget https://repo1.maven.org/maven2/org/checkerframework/dataflow/2.5.7/dataflow-2.5.7.jar
+wget https://repo1.maven.org/maven2/org/checkerframework/javacutil/2.5.7/javacutil-2.5.7.jar
+wget https://repo1.maven.org/maven2/com/google/code/findbugs/jFormatString/3.0.0/jFormatString-3.0.0.jar
 javac \
   -XDcompilePolicy=simple \
-  -processorpath error_prone_core-2.3.2-with-dependencies.jar \
+  -processorpath error_prone_core-2.3.2-with-dependencies.jar:dataflow-2.5.7.jar:javacutil-2.5.7.jar:jFormatString-3.0.0.jar \
   '-Xplugin:ErrorProne -XepDisableAllChecks -Xep:CollectionIncompatibleType:ERROR' \
   ShortSet.java
 ```
@@ -229,12 +236,15 @@ ShortSet.java:8: error: [CollectionIncompatibleType] Argument 'i - 1' should not
 To use Error Prone from the command line as a javac replacement:
 
 ```
-wget https://repo1.maven.org/maven2/com/google/errorprone/javac/9+181-r4173-1/javac-9+181-r4173-1.jar
 wget https://repo1.maven.org/maven2/com/google/errorprone/error_prone_core/2.3.2/error_prone_core-2.3.2-with-dependencies.jar
+wget https://repo1.maven.org/maven2/org/checkerframework/dataflow/2.5.7/dataflow-2.5.7.jar
+wget https://repo1.maven.org/maven2/org/checkerframework/javacutil/2.5.7/javacutil-2.5.7.jar
+wget https://repo1.maven.org/maven2/com/google/code/findbugs/jFormatString/3.0.0/jFormatString-3.0.0.jar
+wget https://repo1.maven.org/maven2/com/google/errorprone/javac/9+181-r4173-1/javac-9+181-r4173-1.jar
 javac \
   -J-Xbootclasspath/p:javac-9+181-r4173-1.jar \
   -XDcompilePolicy=simple \
-  -processorpath error_prone_core-2.3.2-with-dependencies.jar \
+  -processorpath error_prone_core-2.3.2-with-dependencies.jar:dataflow-2.5.7.jar:javacutil-2.5.7.jar:jFormatString-3.0.0.jar \
   '-Xplugin:ErrorProne -XepDisableAllChecks -Xep:CollectionIncompatibleType:ERROR' \
   ShortSet.java
 ```