cleanup

Epochs: integrate ._reject_setup() into .__init__()
ENH: Epochs

Add custom epoch rejection time interval (reject_tmin and reject_tmax
kwargs).
Merge pull request #346 from dengemann/fix_erf_topo

FIX: reordering in topo erfimage 
FIX: reject time window

 - DOC
 - kwarg order
 - don't raise an error for reject_tmin == tmin and reject_tmax == tmax
 - revert to using ._reject_setup() from .__init__()
TST : improve testing of reject_tmin / tmax
Merge branch 'master' of github.com:mne-tools/mne-python
ENH: Better error handling
ENH: Better error for plot_evoked
FIX: correct logic

correct logic for key comparison
Merge pull request #345 from Eric89GXL/plot-catch

ENH: Better error handling for plotting functions
ENH: Improving sample dataset tracking
FIX: Fixing no-directory and no-var bugs
FIX: Fixing sample data path logic
FIX: Removing relative paths in examples
FIX: Adding tests for config
ENH: Adding download status
ENH: Using JSON
FIX: Throw KeyError
ENH+FIX: Adding MEGSIM support, fixing minor testing bug
FIX: Minor fixes