v0.2

New features:

• Add selection-extending jumps
• Add add selection mode (#7)

The two new modes are available with switches:

:jumpJump -add
:jumpJump -extend

Fixes:

• Make viewport not jump on executing the jump
• Use %opt{extra_word_chars} as the default for `jumpExtraWordCharacters
• Fix off-by-one error in labels' byte length calculation
• Add +a attribute to default labels face