libdirect: Add FromString template returning true if conversion succeeded, default implementation returns always false.
libdirect: Add FromString template returning true if conversion succeeded, default implementation returns always false.

deniskropp/DirectFB,jcdubois/DirectFB,sklnet/DirectFB,kevleyski/directfb,kevleyski/DirectFB-1,deniskropp/DirectFB,mtsekm/test,kevleyski/DirectFB-1,sklnet/DirectFB,jcdubois/DirectFB,mtsekm/test,djbclark/directfb-core-DirectFB,kevleyski/DirectFB-1,DirectFB/directfb,kevleyski/directfb,kevleyski/directfb,dfbdok/DirectFB1,deniskropp/DirectFB,DirectFB/directfb,DirectFB/directfb,dfbdok/DirectFB1,kevleyski/DirectFB-1,djbclark/directfb-core-DirectFB,lancebaiyouview/DirectFB,sklnet/DirectFB,kaostao/directfb,kaostao/directfb,sklnet/DirectFB,Distrotech/DirectFB,deniskropp/DirectFB,Distrotech/DirectFB,lancebaiyouview/DirectFB,djbclark/directfb-core-DirectFB,kevleyski/directfb,mtsekm/test,djbclark/directfb-core-DirectFB,lancebaiyouview/DirectFB,lancebaiyouview/DirectFB,dfbdok/DirectFB1,jcdubois/DirectFB,Distrotech/DirectFB,kaostao/directfb