Add a link to the documentation to the README

Fixes #330.
Revert "Merge pull request #327 from ContinuumIO/pypi-install"

This reverts commit 57eaac63d41ede5b8e7527cf32c0aa564400c89d, reversing
changes made to 84ca3b6542ef15ffe2c980fc15f04e9d91da6edc.
Revert "Add changelog additions for pypi-install branch merge."

This reverts commit f51609bc70aa23ccb1962d583eacc5516771ee7d.
Merge pull request #335 from ContinuumIO/revert_pypi_pull

Revert the pull request that merged pypi-install
add the new hidden .nonadmin file
fix creation of directories
fix open mode
update changelog
New fixes to conda for better integration with pip and pypi
Remove unused function.
Don't try to install pip with pip...
handle uncaught exception in conda list
remove sys.prefix workaround (not that the problem has been fixed in Python itself)
remove unused imports and cleanup
avoid deep indentation
fix conda list on Windows
use regex to extract name and version from pip output
strip line
simplified _linked() in main_list
Convert .next() to next(...) for Python 3