Utilities/Sphinx: Add option to build 'singlehtml' format

Add SPHINX_SINGLEHTML to enable the Sphinx 'singlehtml' builder.
Merge branch 'master' into doc-singlehtml

Resolve conflicts in Utilities/Sphinx/CMakeLists.txt by adding the help
options from both sides.
Restore --help-full option to output all help manuals

This option was removed during conversion to the reStructuredText
documentation.  Restore it.  Process documentation starting at
Help/index.rst so that all manuals are included in the output.
CMake Nightly Date Stamp
UseSWIG: Add support for Go and Lua
Merge topic 'doc-full-help'

478356e6 Restore --help-full option to output all help manuals
Merge topic 'doc-singlehtml'

aaa6c8a6 Merge branch 'master' into doc-singlehtml
faf291a9 Utilities/Sphinx: Add option to build 'singlehtml' format
Merge topic 'UseSWIG-go-support'

a3b1be5e UseSWIG: Add support for Go and Lua
regex: Use static regexs where possible

Rather than declaring and compiling a constant regex every time a chunk
of code is executed, build the regex once.
regex: Search on strings where possible
cmTarget: Remove an unused variable
cmMakefile: Use a hashmap for imported targets
Merge branch 'master' into testing/merge

* master:
  UseSWIG: Add support for Go and Lua
  CMake Nightly Date Stamp
  Restore --help-full option to output all help manuals
  Utilities/Sphinx: Add option to build 'singlehtml' format
Merge branch 'dev/hashmap-imported-targets' into testing/merge

* dev/hashmap-imported-targets:
  cmMakefile: Use a hashmap for imported targets
Merge branch 'dev/slicer-profiling' into testing/merge

* dev/slicer-profiling:
  cmTarget: Remove an unused variable
  regex: Search on strings where possible
  regex: Use static regexs where possible
cmGlobalGenerator: Store targets in hash maps
cmTarget: Allow caching of empty genex expansions
genex: Allow genex caching of config genex on single-config generators

The single-config generators do not make $<CONFIGURATION> and $<CONFIG>
generator expressions context-sensitive.
Merge branches 'dev/target-fastpaths' and 'dev/hashmap-imported-targets' into testing/merge

* dev/target-fastpaths:
  genex: Allow genex caching of config genex on single-config generators
  cmTarget: Allow caching of empty genex expansions

* dev/hashmap-imported-targets:
  cmGlobalGenerator: Store targets in hash maps
cmDefinitions: Use a hashmap

It's faster than the bloom filter.