v1.5.4

• Fixed a typo in the "setup.bat"
• Fixed "Check for Updates" link to match the new repo name.
• Patched the uninstaller so it can be used from different drive letter.
• Added "gt_sphere_types.py" to the uninstaller.
• Created "gt_check_updates.py" to better handle updates.
• Changed the "Check For Updates" button in the main menu to call "gt_check_updates.py" instead of a link.
• Fixed issue where unloaded references wouldn't import when using "gtu_import_references" (#15 )
• Added"gtu_remove_references" (#16 )
• Added a missing reload to "gt_tools_menu.mel"