Grand test fixup (#138)

* start fixing up tests

* fix up tests + automate with drone

* fiddle with linting

* messing about with drone.yml

* some more fiddling

* hmmm

* add cache

* add vendor directory

* verbose

* ci updates

* update some little things

* update sig

vendor/github.com/dsoprea/go-png-image-structure/utility.go

@@ -0,0 +1,65 @@
+package pngstructure
+
+import (
+    "fmt"
+    "bytes"
+
+    "github.com/dsoprea/go-logging"
+)
+
+func DumpBytes(data []byte) {
+    fmt.Printf("DUMP: ")
+    for _, x := range data {
+        fmt.Printf("%02x ", x)
+    }
+
+    fmt.Printf("\n")
+}
+
+func DumpBytesClause(data []byte) {
+    fmt.Printf("DUMP: ")
+
+    fmt.Printf("[]byte { ")
+
+    for i, x := range data {
+        fmt.Printf("0x%02x", x)
+
+        if i < len(data) - 1 {
+            fmt.Printf(", ")
+        }
+    }
+
+    fmt.Printf(" }\n")
+}
+
+func DumpBytesToString(data []byte) string {
+    b := new(bytes.Buffer)
+
+    for i, x := range data {
+        _, err := b.WriteString(fmt.Sprintf("%02x", x))
+        log.PanicIf(err)
+
+        if i < len(data) - 1 {
+            _, err := b.WriteRune(' ')
+            log.PanicIf(err)
+        }
+    }
+
+    return b.String()
+}
+
+func DumpBytesClauseToString(data []byte) string {
+    b := new(bytes.Buffer)
+
+    for i, x := range data {
+        _, err := b.WriteString(fmt.Sprintf("0x%02x", x))
+        log.PanicIf(err)
+
+        if i < len(data) - 1 {
+            _, err := b.WriteString(", ")
+            log.PanicIf(err)
+        }
+    }
+
+    return b.String()
+}