Merge pull request #506 from timschofield/develop

Develop
Merge pull request #507 from timschofield/develop

Develop
Adds code comments, adds PageHeader() print for currabrev and categoryid, replaces addTextWarp-left-align with addText, replaces line-drawing a box with Rectangle(), adds 'Prices excluding tax' warning.
Adds code comments, clean-up unneeded variables, simplies and reorder SQL select, reduces if() calls, replaces addTextWarp-left-align with addText, replaces line-drawing a box with Rectangle(), fixes start-date for 'Y/m/d' format, adds start-date for 'Y-m-d' format, adds a summary section for the report, adds ViewTopic and BookMark, adds more NoOfPeriods.
Merge pull request #508 from fahadhatib/develop

Develop