[chroot] Fixed link to distfiles
Made Makefile almost version-independent
Added necessary mkdir to work on git cloned repo
Removed build swipl method of building Chemlogic because it actually does not work
Compile Chemlogic on the Android platform; just like the bootstrapping of SWI-Prolog
Remove extraneous ld-2.19-...so, because ld-linux.so.3 can be used instead.
Rename clean target to chroot-clean, so that this Makefile can be included in a massive Android app Makefile.
Added sub-Makefiles, again
Unfortunately, recursive make is probably necessary.
Added asset file installer, running in UI thread.
Added make target to install chroot-built files into app structure.
Corrected path to the Chemlogic installation.
Added some tiny scripts to determine the versionName (normal app version number -- Android KitKat 4.4.2, Chemlogic 1.0.0) and versionCode (the internal numbering system -- Android 19, Chemlogic 5)
Added version tagging to the chroot environment, so that it can be used to detect the Chemlogic package version and re-install only as necessary.