Add PDFpenPro

Adds a cask for PDFpenPro analogous to the one for PDFpen
Upgrade Zooom to 2.6.0
Merge pull request #5771 from dbingham/pdfpenpro

Add PDFpenPro
Merge pull request #5770 from dbingham/zooom

Upgrade Zooom to 2.6.0
Fix adobe-air-14.0 sha256
Add Volatility v2.4
Merge pull request #5760 from blacktop/volatility

Volatility
Merge pull request #5772 from hswong3i/adobe-air-14.0-sha256

Fix adobe-air-14.0 sha256
Bump appcode version from 3.0.2 to 3.0.4.
Merge pull request #5774 from ctwise/appcode

Bump appcode version from 3.0.2 to 3.0.4.
Update Seafile Client to 3.1.5
Merge pull request #5776 from fragility/seafile

Update Seafile Client to 3.1.5
Update alfred to 2.4_279
Merge pull request #5777 from alebelcor/patch-1

Update alfred to 2.4_279