BuildSystem: Move all userpace libraries under the userspace directory

As the number of libraries is increasing, root directory starts to
expand. This adds better organization for libraries

userspace/libraries/LibC/include/langinfo.h

@@ -0,0 +1,74 @@
+#ifndef _LANGINFO_H
+#define _LANGINFO_H 1
+
+// https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/langinfo.h.html
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+#include <bits/types/locale_t.h>
+#include <nl_types.h>
+
+#define CODESET		0
+#define D_T_FMT		1
+#define D_FMT		2
+#define T_FMT		3
+#define T_FMT_AMPM	4
+#define AM_STR		5
+#define PM_STR		6
+#define DAY_1		7
+#define DAY_2		8
+#define DAY_3		9
+#define DAY_4		10
+#define DAY_5		11
+#define DAY_6		12
+#define DAY_7		13
+#define ABDAY_1		14
+#define ABDAY_2		15
+#define ABDAY_3		16
+#define ABDAY_4		17
+#define ABDAY_5		18
+#define ABDAY_6		19
+#define ABDAY_7		20
+#define MON_1		21
+#define MON_2		22
+#define MON_3		23
+#define MON_4		24
+#define MON_5		25
+#define MON_6		26
+#define MON_7		27
+#define MON_8		28
+#define MON_9		29
+#define MON_10		30
+#define MON_11		31
+#define MON_12		32
+#define ABMON_1		33
+#define ABMON_2		34
+#define ABMON_3		35
+#define ABMON_4		36
+#define ABMON_5		37
+#define ABMON_6		38
+#define ABMON_7		39
+#define ABMON_8		40
+#define ABMON_9		41
+#define ABMON_10	42
+#define ABMON_11	43
+#define ABMON_12	44
+#define ERA			45
+#define ERA_D_FMT	46
+#define ERA_D_T_FMT	47
+#define ERA_T_FMT	48
+#define ALT_DIGITS	49
+#define RADIXCHAR	50
+#define THOUSEP		51
+#define YESEXPR		52
+#define NOEXPR		53
+#define CRNCYSTR	54
+
+char* nl_langinfo(nl_item item);
+char* nl_landinfo_l(nl_item item, locale_t locale);
+
+__END_DECLS
+
+#endif