clarify the use and limitations of META_ADD, META_MERGE
Disregard some warnings during tests when cross-compiling

Previously, tests would fail in cross-compilation builds of perl
because of warnings ala this:

    Warning (mostly harmless): No library found for -lm

This happens because target systems usually have a very limited
selection of libraries to speak of.

This commit has the tests ignore those warnings on a cross-compiled
perl.
Merge pull request #100 from Perl-Toolchain-Gang/topic/docs_201405

clarify the use and limitations of META_ADD, META_MERGE
Backport core change for ExtUtils::Install pm_to_blib
Release engineering for v6.99_01
No longer warn on failed evals in parse_version()
Release engineering for v6.99_02
Update documents.

Rename PATCHING to CONTRIBUTING and rewrite modern.
Delete TODO
According to CONTRIBUTING, fixed README
Rearrange the bundled CPAN-Meta
Merge pull request #102 from magnolia-k/update_docs

Update documents.
Release engineering for v6.99_03
We don't have to say each file that we are manifying so don't
Release engineering for v6.99_04
.gitignore vim swap files.
Allow t/INSTALL_BASE.t to run on >1 install dest.
Add dir-with-space to t/INSTALL_BASE.t - fails.
$CLEANUP var controls whether cleanup done.
Test with 2 spaces in dirname.
Check PERL_MM_OPT does right thing with two spaces as well as one.