Do a large chunk of the move to go

This commit moves a huge chunk of the code to go. The TODO.md document
indicates what is left to be done.

internal/bookkeeping/bookkeeping.go

@@ -0,0 +1,68 @@
+// Package bookkeeping implements reading and writing from the bookkeeping table
+package bookkeeping
+
+import (
+	"database/sql/driver"
+	"errors"
+	"time"
+)
+
+// Instance is a WissKI Instance inside the bookkeeping table.
+// It does not represent a running instance; it does not perform any validation.
+type Instance struct {
+	// NOTE: Modifying this struct requires a database migration.
+	// This should nnever be done unless you know what you're doing.
+
+	// Primary key for the instance
+	Pk uint `gorm:"column:pk;primaryKey"`
+
+	// time the instance was created
+	Created time.Time `gorm:"column:created;autoCreateTime"`
+
+	// slug of the system
+	Slug string `gorm:"column:slug;not null;unique"`
+
+	// email address of the system owner (if any)
+	OwnerEmail string `gorm:"column:owner_email;type:varchar(320)"`
+
+	// should we automatically enable updates for the system?
+	AutoBlindUpdateEnabled SQLBit1 `gorm:"column:auto_blind_update_enabled;default:1"`
+
+	// The filesystem path the system can be found under
+	FilesystemBase string `gorm:"column:filesystem_base;not null"`
+
+	// SQL Database credentials for the system
+	SqlDatabase string `gorm:"column:sql_database;not null"`
+	SqlUser     string `gorm:"column:sql_user;not null"`
+	SqlPassword string `gorm:"column:sql_password;not null"`
+
+	// GraphDB Repository
+	GraphDBRepository string `gorm:"column:graphdb_repository;not null"`
+	GraphDBUser       string `gorm:"column:graphdb_user;not null"`
+	GraphDBPassword   string `gorm:"column:graphdb_password;not null"`
+}
+
+func (i Instance) IsBlindUpdateEnabled() bool {
+	return bool(i.AutoBlindUpdateEnabled)
+}
+
+// SQLBit1 implements a boolean as a BIT(1)
+type SQLBit1 bool
+
+func (sb SQLBit1) Value() (driver.Value, error) {
+	if sb {
+		return []byte{1}, nil
+	} else {
+		return []byte{0}, nil
+	}
+}
+
+var errBadBool = errors.New("SQLBit1: Database does not contain Bit(1)")
+
+func (sb *SQLBit1) Scan(src interface{}) error {
+	if bytes, ok := src.([]byte); ok && len(bytes) == 1 {
+		*sb = bytes[0] == 1
+		return nil
+	}
+	return errBadBool
+}