travis: let cppcheck check most of the repo, but suppress files/warnings that we don't care about via suppression file.

.travis.yml

@@ -20,7 +20,7 @@ script:
 # compile cppcheck, default build
   - make -j4
   - make test -j4
-  - ./cppcheck --error-exitcode=1 -Ilib --enable=style --suppressions-list=.travis_suppressions cli gui lib build test -igui/test -itest/test.cxx
+  - ./cppcheck --error-exitcode=1 -Ilib --enable=style --suppressions-list=.travis_suppressions .
 # compile gui
   - cd gui
   - qmake

.travis_suppressions

@@ -2,3 +2,13 @@ uselessAssignmentPtrArg:build/checkstl.cpp
 assertWithSideEffect:build/checkuninitvar.cpp
 duplicateBranch:build/checkunusedvar.cpp
 duplicateBranch:lib/checkunusedvar.cpp
+*:gui/test*
+*:test/test.cxx
+
+*:democlient*
+*:externals*
+*:htdocs*
+*:htmlreport*
+*:samples*
+*:tools*
+*:win_installer*