Add solutions from my repo

https://github.com/JIghtuse/rosetta
Add descriptions to new files, fix url
Remove unfinished example
Add solution for file size task
Add solution for file renaming
Changes to version 0.10-pre (2780d9 2014-02-09 11:21:22)
Merge branch 'master' of https://github.com/eliovir/rust-rosetta
Update files according to /JIghtuse/rosetta

Add travis button
Fix swap example (swap was moved to std::mem)
add sieve of eratosthenes
add mutual recursion
Merge pull request #10 from eliovir/master

Changes to version 0.10-pre (2780d9 2014-02-09 11:21:22)
Merge pull request #12 from jschaf/mutual_recursion

add mutual recursion
Fix merge commit
Fix merge
Spaces in readme.
extern mod -> extern crate
Update README.md
Hashmap is now in the collections crate
Merge pull request #13 from mvdnes/update_to_master

Hashmap is now in the collections crate