game: cleanup gk's CLI documentation (#2189)

An attempt to cleanup the last CLI interface we have left to cleanup. 
- `gk` args now follow the typical convention ie. `--proj-path` instead
of `-proj-path`.
- args that are passed through to the rest of the application / the
game's runtime use the typical convention of following a `--`
- I'm thinking some args shouldn't be handled at this level ie
(`-nodisplay`, `-vm`, `-novm` or `-jak2`) These could be better
documented as legitimate flags and passed in via a nice struct. They
don't seem to be used in `InitParams` but I'll triple check.

There's a temporary shim here so there is no coupled release with the
launcher (right now it executes `gk` with a few args). So I just change
the old args into the new format. After one release cycle, I can change
it in the launcher and delete it here.

I am unsure if this will break the bash shellscript usages -- not sure
which args were usually passed into `$@`


![image](https://user-images.githubusercontent.com/13153231/222035309-b6601719-cdc9-40ee-b36e-e4b135d3f128.png)

common/util/FileUtil.cpp

@@ -129,6 +129,7 @@ std::optional<std::string> try_get_jak_project_path() {
 
 std::optional<fs::path> try_get_data_dir() {
   fs::path my_path = get_current_executable_path();
+  lg::info("Current executable directory - {}", my_path.string());
   auto data_dir = my_path.parent_path() / "data";
   if (fs::exists(data_dir) && fs::is_directory(data_dir)) {
     return std::make_optional(data_dir);