Move repositories to 'repos/' subdirectory

This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.

Issue #1082

repos/demo/lib/import/import-libpng_static.mk

@@ -0,0 +1 @@
+REP_INC_DIR += include/libpng_static

repos/demo/lib/import/import-libz_static.mk

@@ -0,0 +1 @@
+REP_INC_DIR += include/libz_static

repos/demo/lib/import/import-mini_c.mk

@@ -0,0 +1 @@
+REP_INC_DIR += include/mini_c

repos/demo/lib/mk/launchpad.mk

@@ -0,0 +1,4 @@
+LIBS   = base
+SRC_CC = launchpad.cc
+
+vpath launchpad.cc $(REP_DIR)/src/lib/launchpad

repos/demo/lib/mk/libpng_static.mk

@@ -0,0 +1,12 @@
+SRC_C   = png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c pngread.c \
+          pngrio.c pngwio.c pngwrite.c pngrtran.c pngwtran.c pngmem.c \
+          pngerror.c pngpread.c
+
+CC_OPT += -nostdinc -funroll-loops -DPNG_USER_CONFIG
+LIBS    = mini_c libz_static
+
+CC_WARN = -Wall -Wno-address
+
+vpath % $(REP_DIR)/src/lib/libpng/contrib
+
+include $(REP_DIR)/lib/import/import-libpng_static.mk

repos/demo/lib/mk/libz_static.mk

@@ -0,0 +1,9 @@
+SRC_C   = adler32.c compress.c crc32.c gzio.c uncompr.c deflate.c trees.c \
+          zutil.c inflate.c infback.c inftrees.c inffast.c
+
+CC_OPT += -nostdinc
+LIBS    = mini_c
+
+vpath % $(REP_DIR)/src/lib/libz/contrib
+
+include $(REP_DIR)/lib/import/import-libz_static.mk

repos/demo/lib/mk/mini_c.mk

@@ -0,0 +1,10 @@
+SRC_C  = mini_c.c
+SRC_CC = snprintf.cc vsnprintf.cc atol.cc strtol.cc strtod.cc \
+         malloc_free.cc memcmp.cc strlen.cc memset.cc abort.cc \
+         printf.cc
+
+STDINC = yes
+
+vpath % $(REP_DIR)/src/lib/mini_c
+
+include $(REP_DIR)/lib/import/import-mini_c.mk

repos/demo/lib/mk/scout_gfx.mk

@@ -0,0 +1,3 @@
+SRC_CC = sky_texture_painter.cc
+
+vpath %.cc $(REP_DIR)/src/lib/scout_gfx

repos/demo/lib/mk/scout_widgets.mk

@@ -0,0 +1,31 @@
+LIBS      = base blit scout_gfx
+SRC_CC    = tick.cc elements.cc widgets.cc scrollbar.cc
+
+SCOUT_DIR = $(REP_DIR)/src/app/scout
+
+INC_DIR  += $(SCOUT_DIR)/include
+
+vpath %    $(SCOUT_DIR)/data
+vpath %.cc $(SCOUT_DIR)
+
+SRC_TFF   =   vera16.tff \
+             verai16.tff \
+              vera18.tff \
+              vera20.tff \
+              vera24.tff \
+            verabi10.tff \
+              mono16.tff
+
+SRC_RGBA  =   uparrow.rgba \
+            downarrow.rgba \
+               slider.rgba \
+                sizer.rgba \
+             titlebar.rgba \
+              loadbar.rgba \
+               redbar.rgba \
+             whitebar.rgba \
+            kill_icon.rgba \
+          opened_icon.rgba \
+          closed_icon.rgba
+
+SRC_BIN = $(SRC_TFF) $(SRC_MAP) $(SRC_RGBA)