Adding experimental tags for new experiments

ext-partition: to hold partition extensions (ex. ext-partition,
ext-coding-unit-size from nextgen)
loop-restore: to hold in-loop restoration filter (ex. loop-postfilter
from nextgen and other Wiener restoration filters)

Change-Id: I71c7f1588f05fb0f2b00f7004a78e90c9cceae3f

configure

@@ -280,6 +280,8 @@ EXPERIMENT_LIST="
     ext_refs
     supertx
     ans
+    loop_restoration
+    ext_partition
 "
 CONFIG_LIST="
     dependency_tracking