implement hofstadter q sequence
update README
add links to the rosetta code pages for align_columns.rs and hofstadter.rs
the ISAAC cipher
isaac cipher
feedback
Merge pull request #215 from pfalabella/isaac-cipher

The ISAAC cipher
implement iterable version of hofstadter q
remove non-iterator version
Update .travis.yml

simplifying, now that rust is a supported language
Merge pull request #217 from pfalabella/patch-1

Update .travis.yml
Added luhn_test.rs
Merge pull request #214 from wenderen/hofstadter_q

implement hofstadter q sequence
Merge pull request #218 from Thiez/thiez-luhn_test

Added luhn_test.rs
fix build (squashed)
Merge pull request #220 from pfalabella/fix-build

fix build
added pernicious numbers and population count
ported comma quibbling
readme
Merge pull request #223 from pfalabella/quibble

Ported Comma quibbling