cppcheck options: add --output-file-type option

[RobertWak]

When used with tools such as cmake, cppcheck doesn't provide an convenient way to output into files.

    I've added two values for new --output-file-type option:

         uniq: this will create a output file name based on the --output-file and the current file(s) that are analyzed
         append: this will open the --output-file file in append mode and add the content to it

            example:
                    Not using the new option:

                        $ cppcheck --enable=all --xml --xml-version=2 --output-file=output_files/cppcheck.xml cli/cmdlineparser.cpp
                        $ ls -la output_files/
                        total 12
                        drwxrwxr-x  2 user user 4096 Jul 22 14:47 .
                        drwxrwxr-x 26 user user 4096 Jul 22 14:36 ..
                        -rw-rw-r--  1 user user 1283 Jul 22 14:47 cppcheck.xml

                    Using the option with value "uniq" for one file:

                        $ cppcheck --enable=all --xml --xml-version=2 --output-file=output_files/cppcheck.xml --output-file-type=uniq cli/cmdlineparser.cpp
                        $ ls -la output_files/
                        total 12
                        drwxrwxr-x  2 user user 4096 Jul 22 14:48 .
                        drwxrwxr-x 26 user user 4096 Jul 22 14:36 ..
                        -rw-rw-r--  1 user user 1283 Jul 22 14:48 cppcheck_cmdlineparser_cpp.xml

                    Using the option with value "uniq" for two files:

                        $ cppcheck --enable=all --xml --xml-version=2 --output-file=output_files/cppcheck.xml --output-file-type=uniq cli/cmdlineparser.cpp cli/cppcheckexecutor.cpp
                        $ ls -la output_files/
                        total 16
                        drwxrwxr-x  2 user user 4096 Jul 22 14:49 .
                        drwxrwxr-x 26 user user 4096 Jul 22 14:36 ..
                        -rw-rw-r--  1 user user 4308 Jul 22 14:49 cppcheck_cmdlineparser_cpp_cppcheckexecutor_cpp.xml

                    Using the option with value "append" for one file on a empty/non-existing file:

                       $ cppcheck --enable=all --xml --xml-version=2 --output-file=output_files/cppcheck.xml --output-file-type=append cli/cmdlineparser.cpp
                       $ ls -la output_files/
                       total 12
                       drwxrwxr-x  2 user user 4096 Jul 22 14:51 .
                       drwxrwxr-x 26 user user 4096 Jul 22 14:36 ..
                       -rw-rw-r--  1 user user 1283 Jul 22 14:51 cppcheck.xml

                    Using the option with value "append" for two files on a empty/non-existing file:

                       $ cppcheck --enable=all --xml --xml-version=2 --output-file=output_files/cppcheck.xml --output-file-type=append cli/cmdlineparser.cpp cli/cppcheckexecutor.cpp
                       $ ls -la output_files/
                       total 16
                       drwxrwxr-x  2 user user 4096 Jul 22 14:53 .
                       drwxrwxr-x 26 user user 4096 Jul 22 14:36 ..
                       -rw-rw-r--  1 user user 4308 Jul 22 14:53 cppcheck.xml

                    Using the option with value twise "append" for one file on a empty/non-existing file:

                       $ cppcheck --enable=all --xml --xml-version=2 --output-file=output_files/cppcheck.xml --output-file-type=append cli/cmdlineparser.cpp
                       $ cppcheck --enable=all --xml --xml-version=2 --output-file=output_files/cppcheck.xml --output-file-type=append cli/cppcheckexecutor.cpp
                       $ ls -la output_files/
                       total 16
                       drwxrwxr-x  2 user user 4096 Jul 22 14:54 .
                       drwxrwxr-x 26 user user 4096 Jul 22 14:36 ..
                       -rw-rw-r--  1 user user 5613 Jul 22 14:55 cppcheck.xml

                    /!\ the file is a pure concatenation of the files created without the "append" value which means that it's no more a valid XML file as it will have twice the "<?xml version="1.0" encoding=

"UTF-8"?>" entry
$ cat output_files/cppcheck.xml


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[RobertWak]

superseeded by #3365

the 3365 git history is much cleaner