Relocate source fiiles to src/ subdirectory

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

tests/Makefile.am

@@ -13,4 +13,4 @@ check_PROGRAMS  = $(TESTS)
 # Ignore warnings about unused result, in e.g. write()
 CFLAGS          = -W -Wall -Wextra -Wno-unused-result
 CPPFLAGS        = -D_GNU_SOURCE
-LDADD           = -L../ ../libuev.la
+LDADD           = -L../src ../src/libuev.la

tests/check.h

@@ -7,7 +7,7 @@
 #include <time.h>
 #include <unistd.h>
 
-#include "../uev.h"
+#include "../src/uev.h"
 
 #define UNUSED(arg) arg __attribute__ ((unused))