Add working sqlite example.

[ScottBailey]

This is a very simple example that adds sqlite from an amalgamation source.

[TheLartians]

Thanks a lot for the extra example, this is an interesting use of the patches command! I'm a bit torn if we should encourage the use of the patches like this as the command still seems to have some issues. Until the command is more mature I think we should still encourage the old way of adding the library without using patches:

Suggested change

	if (sqlite_ADDDED)
	add_library(
	sqlite STATIC
	${sqlite_SOURCE_DIR}/sqlite3.c
	${sqlite_SOURCE_DIR}/sqlite3.h
	${sqlite_SOURCE_DIR}/sqlite3ext.h
	)
	target_include_directories(sqlite PUBLIC SYSTEM "${sqlite_SOURCE_DIR}")
	endif()