Material Design icons

from https://github.com/google/material-design-icons
Some svg files had to be fixed because our convert script
created some weird streaks in them. I loaded the svg files in
Inkscape, rotated the object cw and ccw, and saved as new file.
See also https://github.com/google/material-design-icons/issues/22.
I tried to use the same names as the originals so that it's easier
to find them in the Google repo. I just skipped the _..px suffix.
The _24px files go into the /24/ folder.
The _18px files go into the /18/ folder, and so on.
The dark theme versions of ic_expand_less and ic_expand_more
have been manually tinted light gray.

Created a new hist_search icon based on ic_search but
different color and smaller.

Also removed a few unused images:
ic_fulltextsearch
ic_menu_moreoverflow...
ic_save

Change-Id: I488205e74adb0ef7e7336d643a2ed91d16d52841
Merge "Material Design icons"