Code in core source file which depend upon ID-WSF symbols have been
conditionalized, and each id-wsf source file now include directly its
need string header.
* nearly all C files: change includes for relative paths.
* lasso/id-wsf/id_wsf.h, lasso/id-wsf-2.0/id_wsf_2.h: add top level
public include files for ID-WSF 1.0 and ID-WSF 2.0.
* lasso/id-ff/server.*, lasso/id-ff/session.*, lasso/id-ff/identity.*:
remove most of the code related to ID-WSF and push into
lasso/id-wsf/id_ff_extensions.* and lasso/id-wsf-2.0/identity.c,
lasso/id-wsf-2.0/server.c, lasso/id-wsf-2.0/session.c.
* lasso/id-wsf-2.0/saml2_login.c,
lasso/id-wsf-2.0/saml2_login_private.h: same change but for ID-WSF
2.0 support in SAML2 SSO profile.
* lots of files: Explicitely set all field of initialized structures,
in order to remove -Wno-missing-field-initilizers from needed
compiler options when using -Wall -Wextra.