CRUNCH-12: Fix package names in documentation.
CRUNCH-12: Fix package names in documentation.

Rename packages from com.cloudera.crunch to org.apache.crunch.
Quote apostrophes because Markdown is very picky.
Fix other minor errors.

Signed-off-by: jwills <dc012c22ff7ae8bc8b7e53d4d547e0a4e576667a@apache.org>

rvs/crunch,rvs/crunch,rvs/crunch