Update build-osx.md

Formatting tweak
Update build-osx.md

Link to boost, some clarification in the steps.
alternate listaccounts / GetCredits functions
Merge branch 'optim2-1.5' into moon
Increase Default Block Max Size
Merge pull request #267 from rog1121/Fix-Block-Size

Increase Default Block Max Size
Aim for current block, not depth + 1
Update version.h
Merge pull request #269 from rog1121/1.4-Invalids-Ban

Ban Old Forked 1.4 Peers now that 1.4 Branch has a new version
add caching to CWalletTx::GetAmounts and undo some other changes
Merge branch 'master-1.5' into optim2-1.5
Merge branch 'optim2-1.5' into moon