[Lazarus] Tab/Shift tab and block indentation

[Florian Klämpfl]

When completing code, lazarus takes the Block indent value from the 
editor options for indentions, so for proper indention one sets this 
value to two spaces normally. However, this has the effect that 
tab/shift+tab also un/indents by two spaces. This is often not useful 
when reorganizing code. Is there any way to decouple these two 
behaviors: so that code completion idents by 2, tab/shift+tab by 1? Or 
do I need to adapt lazarus sources?