Simplify rotation

[SchrodingersGat]

• Apply rotation as image operation
• Add 90 degrees to account for x/y flip of printer

Attempting a fix for https://github.com/inventree/inventree-brother-plugin/issues/26

References

• https://github.com/inventree/inventree-brother-plugin/issues/26
• https://github.com/inventree/inventree-brother-plugin/issues/23
• https://github.com/inventree/inventree-brother-plugin/pull/24