Updated book.asciidoc
Made changes to ch05.asciidoc
ch5 orphan transactions and orphan pool
Updated book.asciidoc
Merge branch 'master' into chapter/Chapter5

Conflicts:
	ch05.asciidoc

Fixed line termination
Merge branch 'develop'

Conflicts:
	ch05.asciidoc
Updated book.asciidoc
Merge branch 'develop' and 'Chapter6-Reorg'

Conflicts:
	ch05.asciidoc
Merge branch 'develop'
Merge branch 'develop'
Updated book.asciidoc
Merge branch 'develop'
Made changes to ch06.asciidoc
Made changes to ch07.asciidoc
difficulty targeting, block validation, chain selection
Merge branch 'chapter/Chapter8' into develop
undo CR/LF line ending
Merge branch 'develop'
forks, difficulty target, two new diagrams