Feature Request: "formatter:off" for variables with certain suffix or pattern

Hi,

in our code base we have many occurrences of HTML-Strings and that look like this for e.g.:
```java
String html =
//@formatter:off
"" +
"" +
"" + TimeUtils.formatMinutes(monthResult.effectiveWorkedTimeInMinutes) + "" +
"
" +
"" + actualWorkTimeOutput + "" +
"" +
"";
//@formatter:on
```
So we exclude that kind of variables from formatting by using formatter-on/off-tags. The intention to leave the variable-content unformatted is basically already defined by the variable name as it is "html".

So my feature request is roughly:

Add an option to the Java formatter, that excludes variable contents from being formatted for variable-names that match a certain regex.