typos, timings, removed gg download
addressing @gregcaporaso's comments
added mixed wget/curl command
Fix #168, Fix #1506
fixing errors
sortmerna option for OTU picking added
added fuction build_database_sortmerna
disabled the pre-filter by default
updated default parameters for uclust-based OTU pickers. fixes #1585
fixed error
fixed bug in test
finalized integration of sortmerna in pick_otus
added link to peerj preprint
fixed formatting
fixed typo
erge branch 'master' of https://github.com/biocore/qiime into remote

updating to more recent version of qiime
fixed merge conflicts
BUG: Remove failing_tests.sh

That file is not needed in the repository.

Fixes #1592
Merge pull request #1594 from ElDeveloper/failing-tests

Remove tests/failing_tests.sh
fixed typo