Adds some documentation.
Error checks file operations.
Removes accessors from Editor.

Getters have no business being part of an editor.
Moves get/set String methods out of DiskLruCache.
Makes returned OutputStream rethrow IOExceptions.
Fixes a bug in renameToOrThrow.

Inverted the condition.
Uses deleteOrThrow instead of inline code.
Adds remove logic to example.
Converts journal file format from character to binary.

Primarily this upgrades the version to 2 and converts the journal
file format from a character-based file, to a binary file.
Renames projects and app name.
Adds warning log for cache opening problems.
Updates README
Fixes typo.
Merge pull request #3 from jonathanle/master

Big push to productionize.