Add to_string(long long int) overload to fix OSX compilation

src/string.cc

@@ -319,6 +319,13 @@ InplaceString<23> to_string(long int val)
     return res;
 }
 
+InplaceString<23> to_string(long long int val)
+{
+    InplaceString<23> res;
+    res.m_length = sprintf(res.m_data, "%lli", val);
+    return res;
+}
+
 InplaceString<23> to_string(size_t val)
 {
     InplaceString<23> res;

src/string.hh

@@ -365,6 +365,7 @@ inline Hex hex(size_t val) { return {val}; }
 InplaceString<15> to_string(int val);
 InplaceString<23> to_string(long int val);
 InplaceString<23> to_string(size_t val);
+InplaceString<23> to_string(long long int val);
 InplaceString<23> to_string(Hex val);
 InplaceString<23> to_string(float val);
 InplaceString<7>  to_string(Codepoint c);