use Test::Requires instead of eval
add module versions in `use` for scan-prereqs-cpanfile friendly
document enhancement for pass xt/03_pod_coverage.t
fix deps
remove `use Test::Requires 'DBD::SQLite';` sentences.

because, `use DBD::SQLite;` is written in t/001_basic/001_compile.t,
And basic tests are depends on it.
add .travis.yml
Merge pull request #140 from Songmu/feature/update-deps

Feature/update deps