bugfix for using bear

[questor]

Hi, when using bear (https://github.com/rizsotto/Bear) you get compile_commands.jsons without the command json object but with an "arguments" array. this patch will check if the command object is available and if not create it out of the arguments array:

CompileCommandsCompilationUnitsParser.cpp: (Line 116):
CompilationUnit cu;

        if(cmdJson.find("command") == cmdJson.end()) {
            //no command object available, create one from the arguments object
            auto args = cmdJson["arguments"];
            bool firstRun = true;
            for(json::iterator it = args.begin(); it != args.end(); ++it) {
                if(!firstRun) {
                    cu.compilationCommandStr += " ";
                }
                firstRun = false;
                cu.compilationCommandStr += *it;
            }
        } else {
            cu.compilationCommandStr = cmdJson["command"];
        }

        auto dirPath = TeenyPath::path(cmdJson["directory"].get<std::string>());
        if (dirPath.exists()) {
            dirPath = dirPath.resolve_absolute();

[ddovod]

Hi.
Thank you very much for the advice! I'll add the arguments support soon, until that feel free to use this patch.
I'll close the issue when it lands to the master branch.