issue fixed: RavenDB-2163
used NProgress prgress bar and spinner to "inform" user about loading (when loading time is between 1sec and 10 sec)
used error message to inform user that waiting time is too long (when reaching 10 sec mark)
Merge branch 'master' of https://github.com/ayende/ravendb
after previous work with regina:
fixed the problem with deleted items still being shown at the "all documents" collection after automatic redirect.
Merge branch 'master' of https://github.com/ayende/ravendb into RavenDB-2163
Merge branch 'RavenDB_2282' of https://github.com/maximburyak/ravendb
Minor
Merge branch 'RavenDB_2282' of https://github.com/maximburyak/ravendb
fix issue RavenDb_2362 (Null/Bool colours)
Merge branch 'RavenDB-2362' of https://github.com/ReginaBricker/ravendb
1. added progress bar when json loading
2. nprogress styling changed to be much bigger, also, coloring was changed.
3. removed the spinner.
Merge branch 'master' of github.com:ayende/ravendb
Merge branch 'RavenDB-2163' of https://github.com/maximburyak/ravendb

Conflicts:
	Raven.Studio.Html5/Content/app.css
Avoid leaking a task in tests