Factor out time keeping code into its own module: mono_time.c.

It turns out, `unix_time` is also monotonic, and is used as such, so I've
renamed the new functions to `mono_time_*`.

2018-07-08:
```
00:01 <@irungentoo> the idea used to be that the unix_time() function
  could go backward in time but I think I might have started using it like
  if it could not after I changed it so that it would never go back in time
```

1 files changed, 0 insertions, 15 deletions

diff --git a/toxcore/util.h b/toxcore/util.h
index de493ebe..4c5023cf 100644
--- a/toxcore/util.h
+++ b/toxcore/util.h
@@ -39,21 +39,6 @@ extern "C" {
 #define MIN(a,b) (((a)<(b))?(a):(b))
 #define PAIR(TYPE1__, TYPE2__) struct { TYPE1__ first; TYPE2__ second; }
 
-typedef struct Unix_Time Unix_Time;
-
-Unix_Time *unix_time_new(void);
-void unix_time_free(Unix_Time *unixtime);
-
-// TODO(#405): Use per-tox unixtime, remove unix_time_update, and rename
-// unix_time_update_r to unix_time_update.
-void unix_time_update_r(Unix_Time *unixtime);
-uint64_t unix_time_get(const Unix_Time *unixtime);
-int unix_time_is_timeout(const Unix_Time *unixtime, uint64_t timestamp, uint64_t timeout);
-
-void unix_time_update(void);
-uint64_t unix_time(void);
-int is_timeout(uint64_t timestamp, uint64_t timeout);
-
 /* id functions */
 bool id_equal(const uint8_t *dest, const uint8_t *src);
 uint32_t id_copy(uint8_t *dest, const uint8_t *src); /* return value is CLIENT_ID_SIZE */