Merge pull request #336 from anandpdoshi/hotfix

[minor] [smtp] propagate exceptions
[fix] [minor] hide fields and report filters fixed
[fix] [minor] reportview fix for checkbox filters
Merge pull request #338 from akhileshdarjee/master

[fix] [minor] hide fields and report filters fixed
[report] check mandatory filters in query report
[query-report] abort previous ajax query if refreshed multiple times
Merge pull request #341 from nabinhait/report1

Query Report
Merge develop for release
bumped to version 3.1.0
[permission model] Redesign
[permissions] Added Test Cases
[permission model] Redesign
[permissions] Added Test Cases
[cleanup] [minor] added webnotes.model.delete_doc (module)
[cleanup] [minor] default+cache related
[install] [minor] added flag and ignored cache during install
[minor] started versioning
[minor] first cut bump
[minor] validte if current branch is master while bumping version
[query report] Formatting & Minor UI Fixes