Bug: cindent does not work with C++11 raw string literals

[Mark Lodato]

Recent version of Vim support syntax highlighting for C++11 raw string
literals works great, but indentation still does not work. Instead,
cindent tries to indent the string like it's code.

For example, try to type the following (tested on 7.4.589):

const char* s = R"(
test {
# comment
field: 123
}
)";

As you type, vim will annoyingly move `# comment` and `field:` to the
first column because it thinks they are a preprocessor macro and a
label, respectively.

Any chance this could be fixed?

Thanks!
Mark