HUGE update to SVN with *a lot* of changes: DO MAKE CLEAN!

==========================================================
- The DAE.ExpType is *no more*
- The BackendDAE.Type is *no more*
Both got replaced by DAE.Type!
- The DAE.ExpVar is *no more*
It got replaced by DAE.Var!
Now we have *ONLY ONE* type in the compiler: DAE.Type!


Just to know why I got this done:

BEFORE, the model HumMod took 6m51 seconds to instantiate
adrpo@ida-liu050 ~/dev/OpenModelica/doc/performance/benchmarks/tests
$ time /c/OpenModelica1.8.0-r10584/bin/omc instHumMod.mos > trace.txt 2>&1
real    6m51.354s
user    0m0.000s
sys     0m0.015s

AFTER, the model HumMod takes 47 seconds to instantiate
adrpo@ida-liu050 ~/dev/OpenModelica/doc/performance/benchmarks/tests
$ time ../../../../build/bin/omc instHumMod.mos > mytrace.txt 2>&1
real    0m47.248s
user    0m0.000s
sys     0m0.000s

Is about 8,74468085106383 times faster now.
Basically, before, we were doing DAE.T_* 
-> DAE.ET_* translation for 6 minutes!

I started this work on Friday after the OpenModelica 1.8.0 
got released, so for 4+ days of work I think the result is 
quite OK.



Crash course into the new types (actually old ones from DAE.Type):
==================================================================

1. DAE.Type is not a tuple anymore, instead the optional path
   became DAE.TypeSource which is a list of paths and is now 
   part of *all* the records in DAE.Type.
   
   The needed types from DAE.ExpType got merged into DAE.Type:
   DAE.ET_METATYPE                -> DAE.T_METATYPE
   DAE.ET_FUNCTION_REFERENCE_VAR  -> DAE.T_FUNCTION_REFERENCE_VAR
   DAE.ET_FUNCTION_REFERENCE_FUNC -> DAE.T_FUNCTION_REFERENCE_FUNC

   Some DAE.Type types got split:
   DAE.T_COMPLEX split into DAE.T_COMPLEX for types not extending
   basic types and DAE.T_SUBTYPE_BASIC is now used for types 
   extending basic types.
   
   Some DAE.Type types changed name:
   DAE.T_NOTYPE -> DAE.T_UNKNOWN
   Renamed also the meta-types a bit to make them more homogeneous.
   
   Some DAE.ExpType are gone:
   DAE.ET_OTHER is gone, use DAE.T_UNKNOWN instead!

   Some DAE.Type types changed structure (besides the DAE.TypeSource addition):
   (DAE.T_ARRAY(dim, ty), optPath) -> DAE.T_ARRAY(ty, list<dim>, list<Path>)
   so we now have similar structure for DAE.T_ARRAY and the previous DAE.ET_ARRAY.
   

2. In cases, when matching: 
     Instead of              | Use now:
   -------------------------------------------------------
     DAE.ET_INT()            | DAE.T_INTEGER(source = _)
     DAE.ET_REAL()           | DAE.T_REAL(source = _)
     DAE.ET_BOOL()           | DAE.T_BOOL(source = _)
     DAE.ET_STRING()         | DAE.T_STRING(source = _)
     DAE.ET_ENUMERATION(...) | DAE.T_ENUMERATION(...)
     DAE.ET_COMPLEX(...)     | DAE.T_COMPLEX(...)
     DAE.ET_OTHER(...)       | DAE.T_UNKNOWN(source = _)
     DAE.ET_ARRAY(...)       | DAE.T_ARRAY(...)
   -------------------------------------------------------

3. When constructing values, in the then part or in right
   hand side in equations: 
     Instead of              | Use now:
   -------------------------------------------------------
     DAE.ET_INT()            | DAE.T_INTEGER_DEFAULT
     DAE.ET_REAL()           | DAE.T_REAL_DEFAULT
     DAE.ET_BOOL()           | DAE.T_BOOL_DEFAULT
     DAE.ET_STRING()         | DAE.T_STRING_DEFAULT
     DAE.ET_ENUMERATION(...) | DAE.T_ENUMERATION(...)
     DAE.ET_COMPLEX(...)     | DAE.T_COMPLEX(...)
     DAE.ET_OTHER(...)       | DAE.T_UNKNOWN(source = _)
     DAE.ET_ARRAY(...)       | DAE.T_ARRAY(...)
   -------------------------------------------------------

4. Types.elabType got renamed to Types.simplifyType
   and does some type simplification (instead of the
   previous DAE.T_* -> DAE.ET_* translation).

Feel free to ask me anything if something is unclear.

The code can be further improved (we need better handling 
of DAE.T_ARRAY that has several dimensions instead of one) 
by getting rid of Types.simplifyType/Types.expTypetoTypesType, 
but for now is good enough. Also, functionality for the old
DAE.ET_* handling from Expression*.mo can be merged with the
DAE.T_ handling from Types so we can get rid of duplicate
code too.


git-svn-id: https://openmodelica.org/svn/OpenModelica/trunk/doc@10604 f25d12d1-65f4-0310-ae8a-bbce733d8d8e