Drop ccache. I'm getting a lot of illegal instructions from all kinds of builds. [skip appveyor]

.travis.yml

@@ -8,11 +8,6 @@ python:
 env:
     global:
         - BUILD_RUNTIMES=$HOME/.runtimes
-        - CC="ccache gcc"
-        - CCACHE_NOCPP2=true
-        - CCACHE_SLOPPINESS=file_macro,time_macros,include_file_ctime,include_file_mtime
-        - CCACHE_NOHASHDIR=true
-        - CFLAGS="-g -pipe -fomit-frame-pointer -march=native"
         - PYTHONHASHSEED=random
 
     matrix:
@@ -43,7 +38,7 @@ cache:
     - $HOME/.venv
     - $HOME/.runtimes
     - $HOME/.wheelhouse
-    - $HOME/.ccache
+
 
 before_cache:
     - rm -f $HOME/.cache/pip/log/debug.log

Makefile

@@ -179,7 +179,7 @@ develop:
 # disables the cache.
 # We need wheel>=0.26 on Python 3.5. See previous revisions.
 	time ${PYTHON} -m pip install -U --upgrade-strategy=eager -r ci-requirements.txt
-	GEVENTSETUP_EV_VERIFY=3 time ${PYTHON} -m pip install -v -U --upgrade-strategy=eager -e .[test,dnspython,events]
+	GEVENTSETUP_EV_VERIFY=3 time ${PYTHON} -m pip install -U --upgrade-strategy=eager -e .[test,dnspython,events]
 	${PYTHON} -m pip freeze
 	ccache -s
 	@${PYTHON} scripts/travis.py fold_end install