Add more examples

Merge pull request #131 from haroldo-ok/more-examples

- Add example on how to create a simple platformer movement;
- Improve the diagonal ball bouncing example.

See #84

Set ball width

Merge pull request #128 from haroldo-ok/set-ball-width
Fix #117

Create blocks to execute code every n frames.

Merge pull request #127 from haroldo-ok/every-n-frames
Fix #103

Add example on how to bounce a ball

Merge pull request #126 from haroldo-ok/example-bounce-ball
Fix #123

Fix code generation for `while`/`until` block.

Merge pull request #120 from haroldo-ok/fix-or-operator
Fix #119

Fix collision with itself.

Fixes a bug where using the collision block that was colliding with itself was causing a bBasic compilation error.
Changed so that if the block is configured to check collision with something against itself, it will always return `true`.

Merge pull request #118 from haroldo-ok/fix-collision-with-itself
Fix #116

Fix bug when using the true/false boolean constant block.

Merge pull request #115 from haroldo-ok/fix-boolean-constant
Fix #113

Fix nested block inside `else`

- This adds required line breaks in the generated `else` code;
- This fixes label generation for the `while` block.

Fix #109 

Merge pull request #114 from haroldo-ok/fix-nested-block-inside-else

Merge pull request #108 from haroldo-ok/fix-electron-prompt

Fix bug on Electron where the variable creation dialog wasn't opening when clicking on the "Create variable..." button

Bump version to 0.25.1