Fixes #113 add hook to pretty print code to show in diff in atlascode

[marcellourbani]

Fixes / implements #113

[bwieger-atlassian-com]

Reviewing

[bwieger-atlassian-com]

@marcellourbani great to see this PR. I may have missed something, but it doesn't look quite complete.

[marcellourbani]

@bwieger-atlassian-com my apologies, I did the fix almost immediately but forgot to push it
Should be ok now, also merged main

[mubasis]

@bwieger-atlassian-com I believe I resolved the changes required, but github doesn't seem to think so.
I merged the main branch on this, so should only be left with the relevant changes, for this PR which basically:

• adds an API to register a code formatter for the diff views
  • this is returned from the activate method, so client extensions can use it (see an example implementation here, I use it with my own fork )
• adds a command atlascode.bb.togglediffNormalize to toggle the pretty printer when registered
• adds an icon in the diff view to call it
• adds a parameter to the git content provider to keep track of whether to apply the pretty printer or not before diffing

PS: the final result of this + abaplint is in 113: the ABAP language is case insensitive, so lots of irrelevant changes are shown unless both sides are formatted before being diffed

Thank you
Marcello

[marcellourbani]

comment above was from me, I didn't notice I was logged in with the work account

[marcellourbani]

I believe it's ok now

[marcellourbani]

hope it's ok now