do not use villas::utils namespace by default

common/include/villas/utils.hpp

@@ -219,5 +219,3 @@ std::string decode(unsigned char *input, size_t len);
 } /* namespace base64 */
 } /* namespace utils */
 } /* namespace villas */
-
-using namespace villas::utils;

common/lib/advio.cpp

@@ -36,6 +36,8 @@
 #include <villas/config.h>
 #include <villas/advio.h>
 
+using namespace villas::utils;
+
 #define BAR_WIDTH 60 /**< How wide you want the progress meter to be. */
 
 static int advio_trace(CURL * /* handle */, curl_infotype type, char *data, size_t size, void * /* userp */)

common/lib/hist.cpp

@@ -32,6 +32,8 @@
 #include <villas/config.h>
 #include <villas/table.hpp>
 
+using namespace villas::utils;
+
 #define VAL(h, i)	((h)->low + (i) * (h)->resolution)
 #define INDEX(h, v)	round((v - (h)->low) / (h)->resolution)
 

common/lib/kernel/pci.cpp

@@ -31,6 +31,8 @@
 #include <villas/config.h>
 #include <villas/kernel/pci.h>
 
+using namespace villas::utils;
+
 int pci_init(struct pci *p)
 {
 	struct dirent *e;

common/lib/log_legacy.cpp

@@ -31,6 +31,7 @@
 #pragma GCC diagnostic ignored "-Wunused-result"
 
 using namespace villas;
+using namespace villas::utils;
 
 int log_get_width()
 {

common/lib/table.cpp

@@ -29,6 +29,8 @@
 #include <villas/boxes.hpp>
 #include <villas/log.h>
 
+using namespace villas::utils;
+
 int Table::resize(int w)
 {
 	int norm, flex, fixed, total;

common/tests/unit/advio.cpp

@@ -24,7 +24,6 @@
 
 #include <criterion/criterion.h>
 
-#include <villas/utils.hpp>
 #include <villas/utils.hpp>
 #include <villas/advio.h>