Delete unreasonable .gitignore in Eigen release.

Frame/Source/ThirdParty/eigen3/scripts/buildtests.in

@@ -0,0 +1,22 @@
+#!/bin/bash
+
+if [[ $# != 1 || $1 == *help ]]
+then
+  echo "usage: $0 regexp"
+  echo "  Builds tests matching the regexp."
+  echo "  The EIGEN_MAKE_ARGS environment variable allows to pass args to 'make'."
+  echo "    For example, to launch 5 concurrent builds, use EIGEN_MAKE_ARGS='-j5'"
+  exit 0
+fi
+
+TESTSLIST="@EIGEN_TESTS_LIST@"
+targets_to_make=$(echo "$TESTSLIST" | grep -E "$1" | xargs echo)
+
+if [ -n "${EIGEN_MAKE_ARGS:+x}" ]
+then
+  @CMAKE_MAKE_PROGRAM@ $targets_to_make ${EIGEN_MAKE_ARGS}
+else
+  @CMAKE_MAKE_PROGRAM@ $targets_to_make @EIGEN_TEST_BUILD_FLAGS@
+fi
+exit $?
+