assignments: removed previous tree from .texi to only leave toctree

* compiler_stages/compiler_stages.rst,
* compiler_stages/pthl/pthl.rst,
* compiler_stages/tc_1/tc_1.rst,
* compiler_stages/tc_2/samples.rst,
* compiler_stages/tc_2/tc_2.rst,
* compiler_stages/tc_3/tc_3.rst,
* compiler_stages/tc_4/tc_4.rst,
* compiler_stages/tc_5/options.rst,
* compiler_stages/tc_5/samples.rst,
* compiler_stages/tc_5/tc_5.rst,
* compiler_stages/tc_6/samples/samples.rst,
* compiler_stages/tc_6/tc_6.rst,
* compiler_stages/tc_7/tc_7.rst,
* compiler_stages/tc_8/tc_8.rst,
* compiler_stages/tc_9/tc_9.rst,
* compiler_stages/tc_a/tc_a.rst,
* compiler_stages/tc_b/tc_b.rst,
* compiler_stages/tc_d/tc_d.rst,
* compiler_stages/tc_e/tc_e.rst,
* compiler_stages/tc_i/tc_i.rst,
* compiler_stages/tc_l/tc_l.rst,
* compiler_stages/tc_o/tc_o.rst,
* compiler_stages/tc_r/tc_r.rst,
* compiler_stages/tc_x/tc_x.rst,
* compiler_stages/tc_y/tc_y.rst,
* source_code/project_layout/index.rst,
* tools/gnu_build_system/gnu_build_system.rst,
* tools/modern_compiler_implementation/modern_compiler_implementation.rst,
* tools/tools.rst: here.
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triggered
buildweb

00:01:29