Version 1.0 release to do list

[harry093]

Before releasing GeodePy v1.0 the following needs to be done:

• Standardise names of Transformation objects, etc. (Standardise names of Transformation objects, etc #129)
• Define reverse transformations (Define reverse transformations #127)
• Set up GitHub Actions to replace Travis (Set up GitHub Actions #130)
• Define style guide (Create PEP8-based style guide #128)
• Standardise doc strings
• Create a Users' Guide (from doc strings or see Read the Docs) (Create Users' Guide #131)
• Full test coverage