Support the "name_not_regexp" property in the [suppress_type] section

Support the "name_not_regexp" property in the [suppress_type] section

When writting a suppression specification in which the user wants to
keep a family of types (whose names set is specified by a regular
expression) and suppress/drop all other types, one needs to write
something like:

[suppress_type]
  name_regexp = (?!the-regexp-of-the-types-to-keep)

It would be nicer (like what is done for other properties that take
regular expressions as value in suppression specifications) to be able
to write:

[suppress_type]
  name_not_regexp = the-regexp-of-types-to-keep

This patch does just that.

It augments the abigail::suppr::type_suppression type to make it carry
the new 'name_not_regex' property.  It updates the suppression engine
to take the 'name_not_regex' property into account when interpreting
instances of abigail::suppr::type_suppression.  The parser for type
suppression directives is updated to recognize the new name_not_regexp
property.  The manual has been updated accordingly to describe the new
property.  New regression tests have been added.

	* doc/manuals/libabigail-concepts.rst: Update this to document the
	new name_not_regexp property of the suppress_type directive.
	* include/abg-suppression.h
	(type_suppression::{g,s}et_type_name_not_regex_str): Declare new accessors.
	* src/abg-suppression-priv.h
	(type_suppression::priv::{type_name_not_regex_str_,
	type_name_not_regex_}): Define new data members.
	(type_suppression::priv::{get_type_name_not_regex,
	set_type_name_not_regex, get_type_name_not_regex_str,
	set_type_name_not_regex_str}): Define new member functions.
	* src/abg-suppression.cc
	(type_suppression::get_type_name_regex_str): Fix comments.
	(type_suppression::{set_type_name_not_regex_str,
	get_type_name_not_regex_str}): Define new data members.
	(suppression_matches_type_name): Adapt to support the new
	type_name_not_regex property.
	(read_type_suppression): Support parsing the type_name_not_regexp
	property.
	* tests/data/test-diff-suppr/test42-negative-suppr-type-report-0.txt:
	New test reference output.
	* tests/data/test-diff-suppr/test42-negative-suppr-type-report-1.txt: Likewise.
	* tests/data/test-diff-suppr/test42-negative-suppr-type-suppr-1.txt:
	New test input.
	* tests/data/test-diff-suppr/test42-negative-suppr-type-suppr-2.txt: Likewise.
	* tests/data/test-diff-suppr/test42-negative-suppr-type-v0.{cc, o}: Likewise.
	* tests/data/test-diff-suppr/test42-negative-suppr-type-v1.{cc,
	o}: Likewise.
	* tests/data/Makefile.am: Add the test files above to source
	distribution.
	* tests/test-diff-suppr.cc (int_out_specs): Add the new tests to
	the harness.

Signed-off-by: Dodji Seketeli <dodji@redhat.com>