make travis happy

.travis.yml

@@ -10,14 +10,17 @@ git:
 
 addons:
   apt:
+    sources:
+      - ubuntu-toolchain-r-test
+      - sourceline: 'ppa:kzemek/boost'
     packages:
-      - libboost1.55-dev
-      - libboost-filesystem1.55-dev
-      - libboost-iostreams1.55-dev
-      - libboost-program-options1.55-dev
-      - libboost-regex1.55-dev
-      - libboost-system1.55-dev
-      - libboost-thread1.55-dev
+      - libboost1.58-dev
+      - libboost-filesystem1.58-dev
+      - libboost-iostreams1.58-dev
+      - libboost-program-options1.58-dev
+      - libboost-regex1.58-dev
+      - libboost-system1.58-dev
+      - libboost-thread1.58-dev
       - libssl-dev
       - libmysqlclient-dev
       - libreadline6-dev

dep/boost/CMakeLists.txt

@@ -38,7 +38,7 @@ if (WIN32)
   # On windows the requirements are higher according to the wiki.
   set(BOOST_REQUIRED_VERSION 1.59)
 else()
-  set(BOOST_REQUIRED_VERSION 1.55)
+  set(BOOST_REQUIRED_VERSION 1.56)
 endif()
 
 find_package(Boost ${BOOST_REQUIRED_VERSION} REQUIRED system filesystem thread program_options iostreams regex)