Builtin methods done

[Bram Moolenaar]

With this patch:

> Patch 8.1.2012
> Problem: More functions can be used as methods.
> Solution: Make terminal functions usable as a method. Fix term_getattr().
> Files: runtime/doc/terminal.txt, src/evalfunc.c, src/terminal.c
> src/testdir/test_mksession.vim, src/testdir/test_terminal.vim

I finished making all relevant builtin functions available as methods.
For many functions this works nicely. For some it is not obvious what
argument to use for the base. I tried to keep it predictable. For some
it would just be confusing, thus I didn't add support to use the
function as a method.

Example of useful method chaining:

call readfile("input.txt")
\ ->filter('v:val !~ "^#"')
\ ->map('toupper(v:val)')
\ ->writefile("output.txt")

Let me know if you think using some builtin functions as a method
doesn't work predictably.

--
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of your kids... and your pets.

/// Bram Moolenaar -- Br...@Moolenaar.net -- http://www.Moolenaar.net \\\
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