Rename symbols for standard library compatibility

[diddyholz]

Currently, the SDK is not compatible with a C standard library due to it using some symbols such as "open", "write", "memset". This hinders development and therefore I suggest to rename all conflicting functions, structs and enums to use some form of Prefix to distinguish them from the standard library.

In my branch I added the header name as the prefix, as it is already done in LCD.h or MCS.h. I am open to other naming suggestions as well.

I also added a link to my port of newlib in the "development" documentation.

[TheRainbowPhoenix]

I think it should be better to find other ways. As considered :

• Lephe told about .weak

.weak s make symbol s weak, which has the effect that at link time if you have two definitions the non-weak definition overrides the weak one
Or __attribute__((weak)) in C/C++

• QBoss07 told about alias

aliases is something to consider too. .set name1, name2 in asm and somehting like __attribute__((target)) in C/C++

It also seems to be possible to do "both", could be interesting to have an updated PR on that