Even a simple typo fix can result in a reflow of a whole paragraph, leading to illegible diffs. The majority of text editors supports wrapping the source code to a comfortable width so it makes sense to me to sacrifice the few that do not rather than the unfortunately line-oriented diff tools.

(cherry picked from commit 641f635)

[19.09] doc: Disable wrapping source

Fixes build errors for the third-party mongoose module:
```
In file included from
/nix/store/r5s3w32ahjzdlzsfrhybc3l2qcpi6yb2-libpcap-1.9.0/include/pcap.h:43,
                 from /build/ntopng-2.0/include/ntop_includes.h:93,
                                  from src/HTTPserver.cpp:22:
/nix/store/r5s3w32ahjzdlzsfrhybc3l2qcpi6yb2-libpcap-1.9.0/include/pcap/pcap.h:958: note: this is the location of the previous definition
   #define INVALID_SOCKET -1

src/../third-party/mongoose/mongoose.c:270:13: error: multiple types in one declaration
 typedef int SOCKET;
             ^~~~~~
```