Add possibility to make new branches in web interface

[Viktor-Yakovchuk]

• Gitea version (or commit ref): commit c3aaf5e
• Database (use [x]):
  • PostgreSQL
  • MySQL
  • MSSQL
  • SQLite

Description:

There is the possibility to make a commit with some changes but there are no the possibility to make a new branch. The equivalent to
git checkout -b new_branch_name
Adding this feature will case changes only it templates and adding new js handler because all we need at backend is in the code now.

This is new look of branch in branches page:

This is new form for setting name of new branch:

[jolheiser]

You can create a branch from the UI, however there is no button on the branches page.

Are you intending for this issue to be a feature request for the latter?

[Viktor-Yakovchuk]

I can send pull request with a code I recently have written.