Offset the addresses for global symbols (func & variables) by the base
image of the corresponding module.

- various fixes to follow better the functions definition (nesting,
  subroutines...)
- don't directly parse types referenced by a subprogram, they'll be
  loaded anyway when needed

- put back the block attribute parsing
- added dwarf2_compute_location to properly decode a location (at
  least starting it)

- rewrote all entities loading to make use of new dwarf2_debug_info_t scheme
- commented out the location parsing which is an ugly hack

- add some helpers for the rewrite
- module is now part of the dwarf2_parse_context

Removed unused type references scheme that we'll implement using a
different scheme in next patches.

Merge into a single function the struct/class/union parsing.

- now loading the debug info entries into specific structures
- this will help writing new functions
- this will allow handling of forward references

- added a pool for memory allocation when parsing a compilation unit
- now using the brand new sparse array for the abbrev table

- removed lookup for name for the const modifier
- hard wire dwarf-reference to our pointer types

- we should set the module's symtype upon success
- removed unneeded bRet variable

- AT_byte_size can be larger than a single byte (especially for enums)
- added missing enumeration type parsing

Added types_get_real_type() to get rid of typedef information, and
access the real underlying type.

- NVidia allows "const vec4 = {1.0, 2.0, 3.0, 4.0};", even though
  that's not part of the spec.
- It should be  "const vec4 = vecr4(1.0, 2.0, 3.0, 4.0);"
- This patch fixes this for D3DSIO_DEF and D3DSIO_DEFI.

Decoding already handles signed and unsigned CRLs, so don't duplicate
that in CertCreateCRLContext.

Decoding already handles signed and unsigned certs, so don't duplicate
that in CertCreateCertificateContext.

Remove the unused server_sem variable.