Added RemoveElement

quaternion, improve quat::rotate(vec3, vec3) to gracefully handle corner
cases, and add unit tests for all of these.

requires stuff from lol/math, too.

- removed 510 CR characters
 - removed 26 trailing whitespaces
 - replaced 0 tabs with spaces
 - fixed 15 svn:eol-style properties

Added workbench, for personnal experimentation.

- removed 10 CR characters
 - removed 39 trailing whitespaces
 - replaced 243 tabs with spaces
 - fixed 60 svn:eol-style properties