fix influxdb from being given scientific notation

InfluxDB cannot handle scientific notation, so we have to use bigint to
ensure that it doesn't get it...

CHANGES

@@ -2,6 +2,11 @@ Changelog for ETL-Yertl
 
 {{ $NEXT }}
 
+    [Fixed]
+
+    - Fixed a problem with timestamps on InfluxDB being expressed in
+      scientific notation.
+
 0.037     2017-10-27 17:27:41-05:00 America/Chicago
 
     [Fixed]

lib/ETL/Yertl/Adapter/influxdb.pm

@@ -44,6 +44,7 @@ use List::Util qw( first );
 use IO::Async::Loop;
 use Time::Piece ();
 use Scalar::Util qw( looks_like_number );
+use bigint;
 
 =method new
 

t/adapter/influxdb.t

@@ -148,18 +148,22 @@ subtest 'write ts' => sub {
     );
 
     my $time = time;
+    no warnings 'once';
     local *CORE::GLOBAL::time = sub { $time };
     $db->write_ts( @points );
 
     ok $mock->called, 'mock POST called';
     my $args = $mock->method_arguments;
     is $args->[0], 'http://localhost:8086/write?db=mydb', 'POST URL correct';
-    my @lines = (
-        "cpu_load 5m=1.23 1483228800000000000",
-        "cpu_load 5m=1.25 1483229100000000000",
-        "cpu_load 1m=1.26 " . ( $time * 10**9 ),
-    );
-    is $args->[1], join( "\n", @lines ), 'influxdb line protocol points correct';
+    {
+        use bigint;
+        my @lines = (
+            "cpu_load 5m=1.23 1483228800000000000",
+            "cpu_load 5m=1.25 1483229100000000000",
+            "cpu_load 1m=1.26 " . ( $time * 10**9 ),
+        );
+        is $args->[1], join( "\n", @lines ), 'influxdb line protocol points correct';
+    }
     cmp_deeply { @{ $args }[ 2..$#$args ] },
         { content_type => 'text/plain' },
         'additional options are correct';