More interfaces to the int array compression routines.

* src/misc/intvcomp.cc, src/misc/intvcomp.cc: Add interfaces to
compress vector<int> to vector<unsigned>.
* src/tgbatest/intvcomp.cc: Test them.
* src/sanity/style.test: Refine check to avoid a spurious report.

src/sanity/style.test

@@ -165,7 +165,7 @@ for dir in "${INCDIR-..}" "${INCDIR-..}"/../iface; do
       egrep '(->|[.])size\(\) [=!]= 0|![a-zA-Z0-9_]*(->|[.])size\(\)|(if |while |assert)\([a-zA-Z0-9_]*(->|[.])size\(\)\)' $tmp &&
 	diag 'Prefer empty() to check emptiness.'
 
-      egrep '^[^=]*([+][+]|--);' $tmp &&
+      egrep '^[^=*]*([+][+]|--);' $tmp &&
 	diag 'Take good habits: use ++i instead of i++ when you have the choice.'
 
       grep '[^a-zA-Z0-9_](\*[a-zA-Z0-9_]*)\.' $tmp &&