pmt: Improvements for developers

- Android.bp was written to be included in ROMs/recoveries etc. in Android build system.
 - Macros have been added to simplify feature creation.
 - Some bug fixes (for JSON and pmt).

srclib/libpartition_map/src/PartitionMap.cpp

@@ -20,7 +20,9 @@
 #include <cstring>
 #include <fcntl.h>
 #include <filesystem>
+#ifndef ANDROID_BUILD
 #include <generated/buildInfo.hpp>
+#endif
 #include <iostream>
 #include <libpartition_map/lib.hpp>
 #include <linux/fs.h>