Many fixes/convenience changes

[JustusAdam]

• Uses rust-embed to embed templates into the binary so that it is location independent
• Adds main command line arguments and help text
• Adds the option to pick between generating a runnable binary or a mod
• Adds useful arguments and documentation/help to generated binaries
• Makes paralegal dependency a git dependency
• Changes the name of the main binary/crate to paralegal-compiler so it is less likely to have strange conflicts when installed via cargo install