George Oikonomou a63376f8be Use -Os for CC2538 builds
As discussed in #503, -Os was broken with one of the toolchains
recommended in the platform's README and for that reason we were
using -O2 by default.

This commit sets the default to -Os and updates the README to no
longer recommend the toolchain in question
2014-01-31 20:02:43 +00:00
..
2014-01-31 20:02:43 +00:00