[interchange] Add integration with TravisCI

[Josh Lavin]

commit 9f0d07f4d78f6e4ab4dfd5c329560fd49ae50a29
Author: Josh Lavin <jlavin at endpoint.com>
Date:   Fri Jul 1 13:31:53 2016 -0700

    Add integration with TravisCI
    
    - testing many Perl versions
    - only 6 tests, but it's a start
    - Makefile.PL uses PREREQ_PM for tests dependency on HTML::Entities, so
      older Perls can get this installed first. We aren't using
      BUILD_REQUIRES for this because it isn't supported in the older
      versions of Perl.

 .travis.yml   |   24 ++++++++++++++++++++++++
 MANIFEST.SKIP |    1 +
 Makefile.PL   |    3 +++
 3 files changed, 28 insertions(+), 0 deletions(-)
---
diff --git a/.travis.yml b/.travis.yml
new file mode 100644
index 0000000..6ce4aff
--- /dev/null
+++ b/.travis.yml
@@ -0,0 +1,24 @@
+language: perl
+perl:
+  - "5.8.9"
+  - "5.10.1"
+  - "5.12"
+  - "5.14"
+  - "5.16"
+  - "5.18"
+  - "5.20"
+  - "5.22"
+sudo: false
+before_install:
+  - git clone git://github.com/travis-perl/helpers ~/travis-perl-helpers
+  - source ~/travis-perl-helpers/init
+  - build-perl
+  - perl -V
+  - build-dist
+  - cd $BUILD_DIR
+install:
+  - cpan-install --deps
+script:
+  - perl Makefile.PL force=1 PREFIX=/home/travis/interchange
+  - make
+  - perl test.pl
diff --git a/MANIFEST.SKIP b/MANIFEST.SKIP
index 6e3230e..fce18b5 100644
--- a/MANIFEST.SKIP
+++ b/MANIFEST.SKIP
@@ -67,6 +67,7 @@ _$
 ^run(/|$)
 ^scripts/.*[a-z]$
 ^scripts/initp.PL$
+^\.travis.yml$
 ^win(/|$)
 ^windows(/|$)
 ^work(/|$)
diff --git a/Makefile.PL b/Makefile.PL
index 0bbb7f0..19733f3 100644
--- a/Makefile.PL
+++ b/Makefile.PL
@@ -851,4 +851,7 @@ WriteMakefile(
 	VERSION_FROM => "scripts/interchange.PL",
 	EXE_FILES  => [],
 	CONFIGURE  => \&initialize,
+	PREREQ_PM  => {
+		'HTML::Entities' => 0,
+	},
 );