Revert "Ignore packages with malformed versions or malformed constraints"

This reverts commit 8fe23b418b3c3cad690ea3171bb64a8fac711576.
Revert "Uncomment test for `meteor search` with malformed versions"

This reverts commit cb0811a10acab05528c5404b5ccc708bf7cf238b.
Revert "Correct but failing test for lenient parsing of bad version number"

This reverts commit c496bd716bacc24413cb4f948931eb73eb1309a0.