Support template lookups in strncmp_iw_with_mode

This patch adds support for wild template parameter list matches, similar
to how ABI tags or function overloads are now handled.

With this patch, users will be able to "gloss over" the details of matching
template parameter lists.  This is accomplished by adding (yet more) logic
to strncmp_iw_with_mode to skip parameter lists if none is explicitly given
by the user.

Here's a simple example using gdb.linespec/cpls-ops.exp:

Before
------
(gdb) ptype test_op_call
type = struct test_op_call {
  public:
    void operator()(void);
    void operator()(int);
    void operator()(long);
    void operator()<int>(int *);
}
(gdb) b test_op_call::operator()
Breakpoint 1 at 0x400583: test_op_call::operator(). (3 locations)
(gdb) i b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   <MULTIPLE>
1.1                         y     0x400583 in test_op_call::operator()(int)
                                                   at cpls-ops.cc:43
1.2                         y     0x40058e in test_op_call::operator()()
                                                   at cpls-ops.cc:47
1.3                         y     0x40059e in test_op_call::operator()(long)
                                                   at cpls-ops.cc:51

The breakpoint at test_op_call::operator()<int> was never set.

After
-----
(gdb) b test_op_call::operator()
Breakpoint 1 at 0x400583: test_op_call::operator(). (4 locations)
(gdb) i b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   <MULTIPLE>
1.1                         y     0x400583 in test_op_call::operator()(int)
                                                   at cpls-ops.cc:43
1.2                         y     0x40058e in test_op_call::operator()()
                                                   at cpls-ops.cc:47
1.3                         y     0x40059e in test_op_call::operator()(long)
                                                   at cpls-ops.cc:51
1.4                         y     0x4008d0 in test_op_call::operator()<int>(int*)
                                                   at cpls-ops.cc:57

Similar to how scope lookups work, passing "-qualified" to the break command
will cause a literal lookup of the symbol.  In the example immediately above,
this will cause GDB to only find the three non-template functions.

gdb/ChangeLog:

	* NEWS: Mention new template parameter support for
	locations/completion.
	* cp-support.c (cp_search_name_hash): Break on template parameter
	lists.
	(cp_symbol_name_matches_1): Tell strncmp_iw_with_mode to ignore
	template parameter lists.
	* utils.c (skip_template_parameter_list): New function.
	(strncmp_iw_with_mode): Support "ignoring" of template parameter lists.
	* utils.h (strncmp_iw_with_mode): Add new parameter
	`ignore_template_params'.

gdb/doc/ChangeLog:

	* gdb.texinfo (Debugging C Plus Plus): Document setting breakpoints
	in templates.

gdb/testsuite/ChangeLog:

	* gdb.cp/templates.cc (Foozle, operator<, operator<<): New.
	(main): Add uses of new functions/types.
	* gdb.cp/templates.exp: Add template parameter list tests.
	* gdb.linespec/cpcompletion.exp: Load data-structures.exp.
	(consume, maket, makearg, makefoo, test_makefoo_1, test_makefoo)
	(maketype, makem, test_makem_1, test_makem, template-class-with-method)
	(template-function-foo): New procedures.
	(template-ret-type): Split range completion to account for template
	names completing without template parameter list.
	Change "setting breakpoint without template parameter test" to pass.
	(test_driver): Call template-function-foo test procedure.
	* gdb.linespec/cpls-ops.exp (test_operator_ambiguous): Remove
	template restriction.
	Add new whitespace tests for template functions.
	* gdb.linespec/cpls.cc (foo, a, b, c, d, A, B, NA, NB): New
	template definitions.
	(template_function_foo): New function.
	(main): Call template_function_foo.