Commited main sorting files

Added and commited the main sorting source codes: stdlib_sorting.fypp,
stdlib_sorting_sort.fypp, stdlib_sorting_ord_sort.f90, and
stdlib_sorting_sort_index.fypp. Also commited the revised CMakeLists.txt and
Makefile.manual files needed co compile the library including the new codes.

[ticket: X]

Author: wclodius2

src/CMakeLists.txt

@@ -9,6 +9,10 @@ set(fppFiles
     stdlib_linalg.fypp
     stdlib_linalg_diag.fypp
     stdlib_optval.fypp
+    stdlib_sorting.fypp
+    stdlib_sorting_ord_sort.fypp
+    stdlib_sorting_sort.fypp
+    stdlib_sorting_sort_index.fypp 
     stdlib_stats.fypp
     stdlib_stats_corr.fypp
     stdlib_stats_cov.fypp

src/Makefile.manual

@@ -9,6 +9,10 @@ SRCFYPP =\
         stdlib_quadrature.fypp \
         stdlib_quadrature_trapz.fypp \
         stdlib_quadrature_simps.fypp \
+        stdlib_sorting.fypp \
+        stdlib_sorting_ord_sort.fypp \
+        stdlib_sorting_sort.fypp \
+        stdlib_sorting_sort_index.fypp \
         stdlib_stats.fypp \
         stdlib_stats_corr.fypp \
         stdlib_stats_cov.fypp \
@@ -79,6 +83,15 @@ stdlib_quadrature_trapz.o: \
 	stdlib_quadrature.o \
 	stdlib_error.o \
 	stdlib_kinds.o
+stdlib_sorting.o: \
+	stdlib_kinds.o \
+	stdlib_string_type.o
+stdlib_sorting_ord_sort.o: \
+	stdlib_sorting.o
+stdlib_sorting_sort.o: \
+	stdlib_sorting.o
+stdlib_sorting_sort_index.o: \
+	stdlib_sorting.o
 stdlib_stats.o: \
 	stdlib_kinds.o
 stdlib_stats_corr.o: \