cps_hints to mdwn

Signed-off-by: Jim Pryor <profjim@jimpryor.net>

diff --git a/hints/cps_hint_1 b/hints/cps_hint_1.mdwn
similarity index 100%
rename from hints/cps_hint_1
rename to hints/cps_hint_1.mdwn

diff --git a/hints/cps_hint_2 b/hints/cps_hint_2.mdwn
similarity index 100%
rename from hints/cps_hint_2
rename to hints/cps_hint_2.mdwn

diff --git a/hints/cps_hint_3 b/hints/cps_hint_3.mdwn
similarity index 100%
rename from hints/cps_hint_3
rename to hints/cps_hint_3.mdwn

diff --git a/hints/cps_hint_4 b/hints/cps_hint_4.mdwn
similarity index 100%
rename from hints/cps_hint_4
rename to hints/cps_hint_4.mdwn