addressing brian wolff’s comments

<https://gerrit.wikimedia.org/r/#/c/59405/11/includes/Helpers/WikiChecks.php>
<https://gerrit.wikimedia.org/r/#/c/59405/11/includes/Hooks/Hooks.php>
<https://gerrit.wikimedia.org/r/#/c/59405/11/sql/table-create-gwtoolset-mediawiki-templates.sql>

* added a method that attempts to retrieve TemplateData for a MediaWiki Template,
  which falls back to Config::$mediawiki_templates.
* added GWToolset.namespaces.php
* added logo asset
* added logic and exception handling for bad titles
* changed all references to Exception, where applicable to MWException
* merged complimentary changes from the js branch
* moved environment check to the SpecialPage class
* moved json_last_error check from Mapping.php into its own shared function
* re-factored increaseMemoryLimit() and changed its signature to checkMemoryLimit()
* re-factored increaseMaxImageArea() and changed its signature to checkMaxImageArea()
* re-factored use of db table so that we now rely on an array for the “default”
  template parameters
* re-organized Config.php and added more documentation
* removed db schema hook
* removed jquery.ui from the extension, replaced it with resource loader’s jquery.ui modules
* removed /Helpers/WikiPages.php
* renamed $metadata_mapping_subdirectory to $metadata_mapping_subpage
* renamed $metadata_sets_subdirectory to $metadata_sets_subpage

* Config.php
  - added a $use_UploadStash variable
  - added onCanonicalNamespaces hook
  - added test hook
  - added $title_max_length
  - changed $mediafile_namespace to NS_FILE
  - removed some outdated properties
* functions.php
  - added getTitle() to replace WikiPages::getTitleFromUrl()
  - added stripIllegalTitleChars()
  - re-factored getTitle()
* GWToolset.php
  - added namespace definitions
* GWToolset.i18n.php
  - added gwtoolset-mediawiki-template-does-not-exist
  - modified gwtoolset-api-call-unsuccessful
  - modified getoolset-developer-issue
* Hooks.php
  - added onCanonicalNamespaces()
  - added onUnitTestsList()
* Mapping.php
  - adjusted references in getMappingName() to Config::$metadata_namespace
    so that it gets the namespace as a string using
	Language->getNamespaces()[Config::$metadata_namespace]
* MappingPhpAdapter.php
  - added Title::makeTitleSafe() to the create() method
* MediawikiTemplate.php
  - re-factored getTitle()
  - remove Php\Curl reference
* MediawikiTemplatePhpAdapter.php
  - added Title::makeTitleSafe() to the retrieve() method
  - added $wgScriptPath and urlencode to retrieveTemplateData()
  - adjusted retrieveTemplateData() to include $wgServer in api path
    and display $Status message when an error is thrown
* MetadataDetectForm.php
  - adjusted references to Config::$metadata_namespace so that it gets the
    namespace as a string from
    $SpecialPage->getLanguage()->getNamespaces()[Config::$metadata_namespace]
  - added a bit of logic to determine correct fields to display depending on the
    Config::$use_UploadStash setting
* MetadataDetectHandler.php
  - augmented the processRequest() logic for storing/retrieiving XML from
    ContentHandler or the UploadStash
* MetadataMappingHandler.php
  - augmented the processMetadata() logic for storing/retrieiving XML from
    ContentHandler or the UploadStash
* MetadataMappingForm.php
  - added metadata-stash-key hidden input field
* SpecialGWToolset.php
  - added $this->setHeaders()
* UploadHandler.php
  - added expiry option to the stashFile() call, a future option User:Aaron_Schulz is adding
  - added getMetadataFromStash()
  - added saveMetadataFileAsStash()
  - added Title::makeTitleSafe to
    saveMediafileAsContent(), saveMediafileViaJob(), saveMetadataFileAsContent()
  - added use of stripIllegalTitleChars()
  - re-factored saveMetadataFileAsContent()
  - changed getTitleFromFileOrUrl to getTitleFromUrlOrFile, which corresponds to
    the way it processes the two fields from the HTML form
  - re-factored evaluateMediafileUrl(), adding getFileExtension(), which uses
    $wgFileExtensions and MimeMagic to determine and evaluate valid media-file types and extensions
* WikiChecks.php
  - removed verifyCurlExists()
  - removed checkMaxUploadAndIniSettings()
* WikiPages
  - removed titleCheck()
* XmlHandler.php, XmlDetectHandler.php, XmlMappingHandler.php
  - removed the $xml_source pass by reference

Change-Id: I7145a28b3b0b8c94dc901972c9ae088efed2e151