Don't use boost regex lib on travis

.travis.yml

@@ -8,10 +8,9 @@ addons:
     sources:
     - ubuntu-toolchain-r-test
     packages:
-    - libboost-regex-dev
     - g++-5
 
 install:
 - export CXX="g++-5"
-- script/configure -D USE_BOOST_REGEX=true -D USE_LIBPROFILER=false
+- script/configure -D USE_LIBPROFILER=false
 script: script/ci

script/configure

@@ -11,11 +11,6 @@ if [ "$1" == "-h" ]; then
 
 Variables:
 
--D USE_BOOST_REGEX=true
-  Use boost regex library for tests, not the built-in regex library. This is
-  useful when linking against an older version of the standard library.
-  libboost_regex must be installed.
-
 -D USE_LIBPROFILER=false
   Don't link libprofiler into the test binaries. This flag is needed on systems
   where libprofiler (from the google-perftools package) is not installed.

spec/helpers/read_test_entries.cc

@@ -4,17 +4,6 @@
 #include <streambuf>
 #include <dirent.h>
 
-#ifdef USE_BOOST_REGEX
-
-#include "boost/regex.hpp"
-using boost::regex;
-using boost::regex_search;
-using boost::regex_replace;
-using boost::smatch;
-using boost::regex_constants::extended;
-
-#else
-
 #include <regex>
 using std::regex;
 using std::regex_search;
@@ -22,8 +11,6 @@ using std::regex_replace;
 using std::smatch;
 using std::regex_constants::extended;
 
-#endif
-
 using std::string;
 using std::vector;
 using std::ifstream;

tests.gyp

@@ -44,13 +44,8 @@
       ],
       'variables': {
         'USE_LIBPROFILER%': 'true',
-        'USE_BOOST_REGEX%': 'false',
       },
       'conditions': [
-        ['USE_BOOST_REGEX != "false"', {
-          'defines': ['USE_BOOST_REGEX'],
-          'libraries': ['-lboost_regex'],
-        }],
         ['USE_LIBPROFILER != "false"', {
           'libraries': ['-lprofiler'],
         }]