If specifying max memory as a percentage of system memory, force calculated value to a string to avoid causing problems with the redis.conf template. Fixes brianbianco/redisio#59.
Adds support to install Redis into a custom location, instead of only installing into /usr/local.
Merge pull request #60 from StudyBlue/memory_percentage

Fix maxmemory as a percentage
Merge pull request #61 from StudyBlue/custom_install_dir

Custom installation directory
Bumps version to 1.6.0 and updates changelog to include latest accepted pull requests.