Remove assertion being failed by IL labels (IL labels do not yet have specific datatypes).

Added stage1_2/Makefile.am weird rule to keep compatible with previous version of automake

Merge

fix definition of pragma.

Fix the state machine that became broken 2 commits ago (when adding support for nested comments)

Add option to control support for nested comments (default is off, as defined in IEC 61131-3 v2)

Add support for nested comments

Fix bug: when checking compatibility between GLOBAL and EXTERNAL variables, must only enforce GLOBAL CONSTANT => EXTERNAL CONSTANT.
Reverse CONSTANT implication is not enforced, and neither is RETAIN compatibility.

merge

Fix bug: correctly generate code when accessing external variables declared inside FBs as a structured variable (realvar := fb1.fb2.extvar1.realvar)

Fix bug in standard: standard does not allow multiple VAR_GLOBAL ... END_VAR constructs in configurations and resources. This is probably a bug, so we allow it.

Code cleanup (part 3): generate_c_typedecl_c is no longer needed for code generation in POUS.c It is now only needed for datatype declaration in POUS.h

Code cleanup (part 2): generate_typedecl_c now only prints to POUS.h !

Code cleanup (part 1): subrange check functions are now declared in POUS.h (as static inline functions or #define)