Do not use Chocolatey in Appveyor

Check of default Chocolatey feed fails from time to time. And this check
was done for each build, even if Maven was already installed.

Also by removing usage of Chocolatey we receive less files for cache,
and can automatically select Apache mirror.

Author: Godin

appveyor.yml

@@ -6,14 +6,21 @@ branches:
 
 cache:
   # Note that we don't use cache for local Maven repository - see https://github.com/SonarSource/sonar-java/pull/525
-  - C:\ProgramData\chocolatey\bin -> appveyor.yml
-  - C:\ProgramData\chocolatey\lib -> appveyor.yml
-  - C:\bin\apache-maven-3.2.5 -> appveyor.yml
+  - C:\Users\appveyor\maven -> appveyor.yml
 
 install:
   - set MAVEN_VERSION=3.2.5
-  - choco install maven -version %MAVEN_VERSION%
-  - set PATH=%PATH%;C:\bin\apache-maven-%MAVEN_VERSION%\bin
+  # Note that indentation is important here:
+  - ps: |
+      Add-Type -AssemblyName System.IO.Compression.FileSystem
+      if (!(Test-Path -Path "C:\Users\appveyor\maven" )) {
+        (new-object System.Net.WebClient).DownloadFile(
+          "http://www.apache.org/dyn/closer.cgi?action=download&filename=maven/maven-3/$($env:MAVEN_VERSION)/binaries/apache-maven-$($env:MAVEN_VERSION)-bin.zip",
+          "C:\Users\appveyor\maven.zip"
+        )
+        [System.IO.Compression.ZipFile]::ExtractToDirectory("C:\Users\appveyor\maven.zip", "C:\Users\appveyor\maven")
+      }
+  - set PATH=%PATH%;C:\Users\appveyor\maven\apache-maven-%MAVEN_VERSION%\bin
   - echo %JAVA_HOME%
   - if "%RUN%" == "ruling" (git submodule update --init --recursive)