Add Java code samples for replacement with infotype

[jakubrauch]

To be linked from https://cloud.google.com/dlp/docs/redacting-sensitive-data

Fixes #issue

It's a good idea to open an issue first for discussion.

• [yes] I have followed Sample Format Guide
• [yes] pom.xml parent set to latest shared-configuration
• [nothing new] Appropriate changes to README are included in PR
• [nothing new] API's need to be enabled to test (tell us)
• [nothing new] Environment Variables need to be set (ask us to set them)
• [yes] Tests pass: mvn clean verify required
• [yes] Lint passes: mvn -P lint checkstyle:check required
• [fails] Static Analysis: mvn -P lint clean compile pmd:cpd-check spotbugs:check advisory only
• [yes] Please merge this PR for me once it is approved.