Add attributes method to get attributes for element

[digitronik]

No description provided.

[digitronik]

CI will pass after #236

[codecov]

Codecov Report

Merging #237 (5660636) into master (ff2c223) will increase coverage by 0.03%.
The diff coverage is 100.00%.

❗ Current head 5660636 differs from pull request most recent head 2577847. Consider uploading reports for the commit 2577847 to get more accurate results

@@            Coverage Diff             @@
##           master     #237      +/-   ##
==========================================
+ Coverage   86.42%   86.45%   +0.03%     
==========================================
  Files          18       18              
  Lines        2564     2570       +6     
==========================================
+ Hits         2216     2222       +6     
  Misses        348      348              

Flag	Coverage Δ
unittests	86.45% <100.00%> (+0.03%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/widgetastic/browser.py	75.51% <100.00%> (+0.27%)	⬆️

[LightOfHeaven1994]

LGTM, great!