llvm_c_ext: Improved `LLVMSetMetadata2()` to support also function values ...in addition to instruction values. This is handy to attach data to functions, such as debugging information. Added Smalltalk API for setting metadata nodes on instructions and functions.

syntax: glob
*Init.c   
makefile
*.so
*.H
*.o
*.STH
*.sc
objbc
objvc
*.class
java/libs/*.jar
java/libs-src/*.jar
*-Test.xml
st.chg

# llvm_c_ext build by-products
*.a
llvm_c_ext/test/test_intrinsics