[FEATURE] Make it possible to select between GL Core and GL ES APIs at instance creation

[kblaschke]

Please confirm the following points:

• This feature request is NOT for the Android apps in the Play Store
• I have searched the project page to check if a similar request was already made

Application or Project

libprojectM (including the playlist library)

Is Your Enhancement Related to a Problem?

Currently, developers must decide to use either GL Core profile or the GL Embedded Standard at compile time, so an application that may need to use either one depending on the environment has to ship with two separate libraries.

Your Suggested Enhancement

Add a new API call that enables the application to choose a specific GL profile for the instance. Alternatively, projectM could try to determine the proper GL variant by querying the current context GL version. This is also necessary for the original projectm_create() method, which will be used by applications that have adopted projectM before version 4.2.

Alternative Solutions

Don't add any additional API functions, and only rely on context detection. Keeps the API slim, but removes some control from application, e.g. to prevent using the wrong GL variant in some edge cases.

Additional Context

No response