update all examples updates for other platforms

[artificiel]

I am giving a stab at streamlining the "install from git" instructions, and for the first time I tried "update multiple".

it's mostly harmless but I found it surprising (and could end up confusing) that all directories including eg android are preprocessed for a Xcode platform.

would a form of filter/map be possible to only process the relevant example for a given platform?

[dimitre]

Yes good idea. PG it is now using fs::recursive_directory_iterator so it is getting everything with a src folder inside. it is possible to program to ignore "android / ios / tvOS" folders. I prefer not hardcode out this folders. As an alternative idea: we could have different examples folders for this unique platforms. Folders like this three have a different nature than the other ones, they are not multiplatform so maybe they could live in other folders in git repository, like:

$ofw/examples_android/all
$ofw/examples_ios/ios
$ofw/examples_ios/tvOS

there is another funny thing that happens: if you compile one example using make, make creates an obj folder with a src folder inside and then you execute PG recursively over examples it will be creating some projects inside obj folder also.