API changes and normalization

[cqcallaw]

Changes:

• Make the API less awful with descriptive return values from pagein and pageout
• Make the API less awful with descriptive page state information in the input to pageit
• Whitespace and formatting normalization
• Merge READMEs

I did my best to make the commits granular enough that the diffs are comprehensible: no ball-of-mud commits here, with the possible exception of the whitespace and formatting normalization commit. The API changes are documented in the header file, but the writeup has not been changed, and the API test hasn't been modified beyond getting it to build. I thought it best to make the changes to the writeup once the API changes have been reviewed and merged.

The basic pager works fine, and I modified my LRU implementation to work with the new API as well. Obviously I don't want to provide the LRU implementation here, but it is available upon request.