Updated tests to add back PHP 7.0

Homebrew/homebrew-core#26026

.travis/clean.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-for version in '5.6' '7.1' '7.2';
+for version in '5.6' '7.0' '7.1' '7.2';
 do
     brew unlink php@$version;
 done

.travis/install.sh

@@ -5,6 +5,8 @@ if [[ $TRAVIS_OS_NAME == 'osx' ]]; then
     brew update
     brew install [email protected]
     brew unlink [email protected]
+    brew install [email protected]
+    brew unlink [email protected]
     brew install [email protected]
     brew unlink [email protected]
     brew install [email protected]

.travis/test.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 
 error=0
-for version in '5.6' '7.1' '7.2'
+for version in '5.6' '7.0' '7.1' '7.2'
 do
     . `echo $(dirname $0)"/../phpswitch.sh"` $version -s > /dev/null
     switched=$(php -v | grep -e '^PHP' | cut -d' ' -f2 | cut -d. -f1,2)