made eso remote test remote
moved all pkg-specific *.rst documents into their own dirs.

this fixes #292.
moved gallery.rst back to parent dir
fix links to moved files in index.rst
Merge pull request #296 from derdon/issue292

moved rst documents to their own directories (see issue #292)
Merge pull request #295 from keflavich/eso_remote

Minor bug fix: Make ESO remote tests remote
Implemented BaseQuery.request() with caching
Do not cache QueryWithLogin.login()
Updated login() of Ukidss
Eso package upgrade

Use baseQuery.request()
Use StringIO, BytesIO from io package
Fixes for python2.6: “{0}”.format()
Do not cache data_retrieval(), save fits files in cache
Added get_header() to Eso package.
Setup eso tests package.
Updated Eso tests, removing @remote_data
Turned Eso tests into a package.
Added data cache for Eso tests.