Rename library version properties for use in Velocity.

  - Since Velocity can't use variables with dots, these library
  version properties should not use them so we can use them in .vm
  manual pages.
Use jackson2Version property.
Use Log4jReleaseVersion variable.
Fix link and invalid Velocity variable.
Use Log4jReleaseVersion variable and fix $dollar stuff.
Update layouts manual page with updated javadoc links.

  - Added javadoc macro for JavaSE links.
  - Updated downloads.oracle.com links to docs.oracle.com.
  - Added link to AnsiEscape.
  - Added ${Charset} variable for frequently repeated javadoc link.