Merge pull request #111 from ChillingVan/dev

v1.5.4

Fix viewport w and h error.

增加高斯模糊滤波器; Add GaussianBlurFilter

Merge pull request #109 from ChillingVan/dev

[v1.5.3]flip horizontally

[v1.5.3]Readme

[v1.5.3]Delete useless code; Convert some files to kotlin

Rename .java to .kt

[v1.5.3]migrate to AndroidX; Update library versions and AGP versions

Merge branch 'dev' of github.com:ChillingVan/android-openGL-canvas into dev

Merge pull request #106 from zatrit/master

Merge branch 'master' into dev

Added jitpack config

Added horizontal flip