Adding link to Ruby implementation

I had added this link on the wiki, but when the page got moved over to GitHub, the link disappeared.
Merge pull request #2 from wink/patch-1

Adding link to Ruby implementation of BIP0032
Merge pull request #1 from laanwj/master

Update BIP-0001 for github move
update to latest BIP-0039 draft
Merge pull request #3 from trezor/master

update to latest BIP-0039 draft
Extend description of the partial merkle block format
Update bip-0013.mediawiki

Clarified that the 4-byte checksum is from double SHA256 rounds
PBKDF2 uses 2048 rounds
Adding link to Go implementation
Merge pull request #8 from WeMeetAgain/patch-1

Adding link to Go implementation of BIP0032
Link to Sarchar's JavaScript BIP32 implementation.
Merge pull request #7 from sarchar/master

Link to Sarchar's JavaScript BIP32 implementation.
Merge pull request #6 from discretepackets/patch-1

Update bip-0013.mediawiki
Add Type field to table in README

I thought it would be nice to enable people browsing BIPs to be able to
tell at a glance which ones are standards track and which are
informational.
Merge pull request #9 from elidourado/master

Add Type field to table in README
Restructured, fixed some grammar/spelling errors.
Fixed table cell truncation

Added spaces after cells in the first column of the `PaymentDetails` table because their contents were being truncated by GitHub's markdown renderer.
fix typo
Merge pull request #11 from matiu/fix-type-at-bip0010

fix typo at bip0010
Merge pull request #10 from brotchie/master

Fixed table cell truncation in BIP 70