Add preprocessFilename hook

For sanitizing filenames added to the grid
Merge branch 'dev' of https://github.com/CenterForOpenScience/hgrid into dev
Prevent extra lazy loading on expandItem.
Use travis config from dev.
Merge branch 'master' into dev

Conflicts:
	dist/hgrid-nodeps.min.js
	dist/hgrid.min.js
Fix typechecking against undefined
Merge branch 'master' into dev

Conflicts:
	dist/hgrid-nodeps.min.js
	dist/hgrid.min.js
Fix for #93 and https://github.com/CenterForOpenScience/openscienceframework.org/issues/723
Merge branch 'dev' of https://github.com/CenterForOpenScience/hgrid into feature/draggable-fixes
Took this line out because I was trying it as a fix and it's unnecessary.