[doc] Update sphinx-extensions submodule.
[dfmc-optimization] Control dispatch behavior via environment variables.

Let partial dispatch and dispatch profiling be controlled by
OPEN_DYLAN_PARTIAL_DISPATCH and OPEN_DYLAN_PROFILE_ALL_CALLS
respectively.
Merge pull request #758 from waywardmonkeys/switch-to-env-vars

[dfmc-optimization] Control dispatch behavior via environment variables.
Update for format-to-string changes.
[dfmc,dfm output] Clearly indicate CONGRUENT-CALLs.

In practice, this changes CALLi to CONGRUENT-CALLi.

This helps make it clear that a congruent call is happening rather
than a fully generic dispatch (CALLg, etc). This also makes it match
the terminology used in the run-times and generated code more
closely.
Merge pull request #759 from waywardmonkeys/debug-back-end-congruent-call

[dfmc,dfm output] Clearly indicate CONGRUENT-CALLs.
[dylan] Typo correction: fols -> fold
[cbe] Add comment saying what version of Open Dylan generated the code and for what platform.
Merge pull request #760 from waywardmonkeys/c-back-end-identification-info

[cbe] Identify Open Dylan version & target platform that generated code
[environment-protocols] Fix ambiguity in find-environment-object.
Merge pull request #764 from fracek/find-environment-object-definition-id

[environment-protocols] Fix ambiguity in find-environment-object.
[dfmc-environment-database] Fix ambiguity for environment-object-name.
Merge pull request #765 from fracek/fix-ambiguous-method

[dfmc-environment-database] Fix ambiguity for environment-object-name.
[crt] MMAllocMisc must call GC_MALLOC_UNCOLLECTABLE, not GC_MALLOC_ATOMIC.
Experimental Unicode database generator

Currently only generates inefficient name tables,
but it already collects lots of useful character properties.
File header fixes

Also grant copyright to the project.
Script for downloading UNIDATA
Merge pull request #766 from promovicz/unicode-data-generator

Experimental Unicode database generator
unicode: simplified representation of general category
unicode: simple TODO