Fix illegal state exception when closing application, fixes sarxos#97

Stop WebcamPanel doesn't stop all required threads, fixes sarxos#90

Add image transformation feature, closes sarxos#73

[maven-release-plugin] copy for tag webcam-capture-parent-0.3.9

[maven-release-plugin] copy for tag webcam-capture-parent-0.3.8

[maven-release-plugin] copy for tag webcam-capture-parent-0.3.7

[maven-release-plugin] copy for tag webcam-capture-parent-0.3.6

[maven-release-plugin] copy for tag webcam-capture-0.3.5

[maven-release-plugin] copy for tag webcam-capture-0.3.4

[maven-release-plugin] copy for tag webcam-capture-0.3.3