Fixed inconsistent hyphenation of "blockchain".

"blockchain" and "block-chain" are used inconsistently on this page.  "blockchain" seems to be used more frequently on the site, so that's the one I went with.

Also, "blockchain-based" should be a hyphenated adjective.
Fixed pluralization in bitshares-ags.php

"all derivative software products to initialize their blockchain" is ambiguous; it is unclear from the wording whether all derivative software products share a single blockchain, or if each one has its own.
Fixed punctuation errors

- Missing period at end of sentence.
- Run-on sentence.
Fixed run-on sentence on PTS page.
Added quotes around identifier.
Made capitalization consistent.

List items under Bitcoin negatives were not Titlecased.
Made capitalization consistent, part 2.
Fixed hyphenation.

'blockchain-based' s/b a hyphenated adjective.
Made DAC reference consistent.

On the rest of the site, the phrase 'Decentralized Autonomous Company' is always Titlecased and suffixed with its abbreviation in parenthesis.
Fixed a run-on sentence.
Added a missing comma.

See http://english.stackexchange.com/q/108122/12664
Merge pull request #71 from todofixthis/master

Misc typo fixes on multiple pages.