chore: tidied up a little

[RohanTalip]

• (Mostly) automatically reformatted code using IntelliJ IDEA to match the Google Style Guide (as documented in CONTRIBUTING.md).
  • 2 space indent, where it wasn't already.
  • Line wrap at 100 characters, where it wasn't already.
  • Wildcard imports were replaced with explicit imports.
  • Unused imports were removed.
  • Annotations were put onto their own line, and additional lines added for readability where necessary.
  • Braces were added to if-statements that didn't already have them.
• Also made some minor edits, e.g. as suggested by IntelliJ IDEA (e.g. public --> private).

This will help with getting the code into shape before style conformance is required as per issue #472 and pull request #496.

See also:

• https://github.com/google/google-java-format
• https://plugins.jetbrains.com/plugin/8527-google-java-format
• https://github.com/google/styleguide/blob/gh-pages/intellij-java-google-style.xml

Checklist

• I have made a material change to the repo (functionality, testing, spelling, grammar)
• I have read the [Contribution Guide] and my PR follows them.
• I updated my branch with the development branch.
  • Not applicable. There is no development branch yet.
• I have added tests that prove my fix is effective or that my feature works
  • Not applicable.
• I have added necessary documentation about the functionality in the appropriate .md file
  • Not applicable.
• I have added in line documentation to the code I modified
  • Not applicable.