feat: add variables, maths and comparison blocks

[razvan-pro]

This change is 

[codecov[bot]]

Codecov Report

Merging #1270 (050bbfb) into master (1db4753) will decrease coverage by 0.23%. The diff coverage is 58.33%.

@@            Coverage Diff             @@
##           master    #1270      +/-   ##
==========================================
- Coverage   91.82%   91.58%   -0.24%     
==========================================
  Files          98       99       +1     
  Lines        5457     5493      +36     
==========================================
+ Hits         5011     5031      +20     
- Misses        446      462      +16     

Impacted Files	Coverage Δ
game/migrations/0076_add_new_blocks.py	58.33% <58.33%> (ø)
game/random_road.py	91.00% <0.00%> (-0.36%)	:arrow_down:

[codecov[bot]]

Codecov Report

Merging #1270 (b18dd9c) into master (daec981) will decrease coverage by 0.35%. Report is 1 commits behind head on master. The diff coverage is 63.93%.

:exclamation: Current head b18dd9c differs from pull request most recent head c496ef0. Consider uploading reports for the commit c496ef0 to get more accurate results

@@            Coverage Diff             @@
##           master    #1270      +/-   ##
==========================================
- Coverage   91.87%   91.53%   -0.35%     
==========================================
  Files         107      108       +1     
  Lines        5636     5657      +21     
==========================================
  Hits         5178     5178              
- Misses        458      479      +21     

Files	Coverage Δ
game/migrations/0083_alter_block_block_type.py	100.00% <100.00%> (ø)
game/models.py	95.45% <ø> (ø)
game/views/level.py	73.75% <84.61%> (+0.73%)	:arrow_up:
...rations/0079_populate_block_type_add_cow_blocks.py	78.26% <16.66%> (-21.74%)	:arrow_down:
game/migrations/0084_add_new_blocks.py	60.52% <60.52%> (ø)

... and 3 files with indirect coverage changes