Update ch01.asciidoc

Typo fixes.
typo fixes
Update ch03.asciidoc

typo fixes
Update ch02.asciidoc

Fixed a typo and changed the definition for when "first confirmation" occurs (according to information from: https://en.bitcoin.it/wiki/Confirmation).
Merging the latest from erikwam:patch-1 (pull request #11)
Merge branch 'erikwam-patch-1' into develop
Merging from arikwam:patch-2 (pull request #12
Merge branch 'erikwam-patch-2' into develop
Merging latest from erikwam:patch-3 (pull request #13)
Merge branch 'erikwam-patch-3' into develop
Merging latest from erikwam:patch-4 (Pull request #14) except for the issue about transaction confirmation counts, which I forked into Issue #18
Merge branch 'erikwam-patch-4' into develop