packaging: remove hg-ssh.8.html from Inno installer
We don't ship hg-ssh because it requires a python.exe to
run, which we don't ship. So it doesn't make sense to ship
the HTML documentation for this tool.
This change makes the Inno install layout more consistent
with WiX, which doesn't ship this file.
Functionality for removing files has been made generic,
in anticipation of future expansion.
Differential Revision: https://phab.mercurial-scm.org/D7169
Our full contribution guidelines are in our wiki, please see:
https://www.mercurial-scm.org/wiki/ContributingChanges
If you just want a checklist to follow, you can go straight to
https://www.mercurial-scm.org/wiki/ContributingChanges#Submission_checklist
If you can't run the entire testsuite for some reason (it can be
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any files you've modified and run `python contrib/check-commit` on any
commits you've made (for example, `python contrib/check-commit
273ce12ad8f1` will report some style violations on a very old commit).