Add commands to tokenizer for "options" in command line

[MaxineMuster]

I often struggle on the parameters order e.g. when starting a driver like AHT2x:
is it <sda> <scl> <channel temp> <channel hum> ?
or <scl> <sda> <channel hum> <channel temp> ?
or ...

So I like a call with "named" arguments like

SDA=17 SCL=19 chan_h=3 chan_t=4
which is totally equal to
chan_h=3 SCL=19 chan_t=4 SDA=17

So I tried to add some "useful" extension to tokenizer code to allow this sort of arguments.

With this change you can check for options like this:

SDA=<pin-ID or pin name> / type=SHT4x / chan_t=<channel>
   or even str="a string"     // use new TOKENIZER_ALLOW_QUOTES_IN_NAMEDARG_VALUE for this

-SCL <pin-ID or pin name> / -type SHT3x / chan_h <channel>
   or -str "another string"    // will "only" need TOKENIZER_ALLOW_QUOTES

new command are (all will need a default in case the option is not found):
  const char *Tokenizer_GetArgEqualDefault(const char *search, const char *def);
  int Tokenizer_GetArgEqualInteger(const char *search, const int def);
  int Tokenizer_GetPinEqual(const char *search, const int def);

You can also check for a "single" option (like "-v" or "-single_mode")
  bool Tokenizer_IsStringPresent(const char *search);

Added selftest for the new commands, too.

[MaxineMuster]

Streamlined and minimized addition:

Now only args like "-SDA 4 -SCL P5" are possible (removed "XY=9" style)

Only one new function, all others as "optional" functions (enable with "#define TOKENIZER_PARAM_EXTENSION 1"), else they can be used as #defines using the one new function.