LP#1850547: new Angular file-reader component

LP#1850547: new Angular file-reader component

This adds a ControlValueAccessor wrapper around a file
reader form input. Any file loaded via that input is interpreted
as a text file whose lines are to be split into an array on
newlines, with leading and trailng whitespace removed.

Usage is:

<eg-file-reader [(ngModel)]="fileContents">
</eg-file-reader>

Sponsored-by: Evergreen Community Development Initiative
Sponsored-by: Georgia Public Library Service
Sponsored-by: Indiana State Library
Sponsored-by: C/W MARS
Signed-off-by: Galen Charlton <gmc@equinoxinitiative.org>
Signed-off-by: Tiffany Little <tlittle@georgialibraries.org>
Signed-off-by: Bill Erickson <berickxx@gmail.com>