Outdated documentation and build files

[NattyNarwhal]

Many of these date back from Ye Olden Days of .NET 1.1.

• CSharpBuilder/: Outdated Borland project files from 12 years ago, doesn't match the structure of the project nowadays.
• docs/: Just the IRC RFC. Not needed, could be supplemented if need be.
• API_CHANGE: Affects an ancient branch.
• CHANGELOG: Very outdated, somewhat redundant with git log.
• CREDITS: outdated, should be updated or use the copyright comment headers
• FEATURES: outdated
• README: project filesystem structure outdated
• TODO: outdated, should be put into issues?

[meebey]

Great summary of dust but where is the PR?