remove warnings

inline native constants

Make 'stdin', 'stdout' and 'stderr' thread local.

NOTE: Because the java type of those items changed from
PrintWriter/BufferedReader to ThreadLocal<PrintWriter>/ThreadLocal<BufferedReader>
this change is binary backwards compatible. In particular,
code compiled with an earlier version will try to access
'stdout' as 'PrintWriter'.

Inserted reference to Language.pdf

fix Issue#61

instances for Integer and Bool

use function pointers of imported modules - saves 1000 classes and 1.…

…5MB on fregec.jar

Add Semigroupoid type-class

proposed fix for issue#50

Handle strictness annotations better and promote them up to code gene…

…ration