Remove unused argument for file::path_attributes
Allow comparison of text::indent_t
Add indent accessor to document_t
Use document’s indent accessor instead of going via buffer()
Document from content now sets file type and tab settings

Presently we also set file type (and thus indirectly indent settings) when “opening” a document, but I wish to remove that code, so that one can create a document, set all desired settings, and not worry about later code overwriting these settings.
Remove unnecessary call to c_str
Setup indent settings at a higher level

We now setup the indent settings when creating untitled documents where we know the folder, so that we can use potential settings scoped to that folder.

Since the document itself no longer sets this as part of regular buffer setup, we also set it when opening a document with a path, and when changing a document’s file type, although the latter is probably temporary.

Closes #305.
fixup! Account for svn returning relative paths

Turns out the paths are relative to the current working directory, not the working copy.
Store tab size with backups
Improve lstat error message
Improve speed of stopping the document scanner

Closes #1069.