talkatu/talkatu

Add TalkatuHtmlParser that abstracts out the traversal of HTML documents to make it easier to output other formats

Add an iterative html parser which will be used to create pangomarkup and gtktext later.

Testing Done:
Added some unittests and ran them in valgrind. Also created and checked the docs.

Reviewed at https://reviews.imfreedom.org/r/89/
###############################################################################
# Options
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option(
'nls',
type : 'boolean', value : true,
description : 'Install translation files'
)
option(
'doc',
type : 'boolean', value : true, yield : true,
description : 'build documentation with gtk-doc'
)
option(
'help2man',
type : 'boolean', value : true,
description : 'Whether or not to build man pages from --help output'
)
option(
'introspection',
type : 'boolean', value : true, yield : true,
description : 'build gobject-introspection support'
)
option(
'tests',
type : 'boolean', value : true,
description : 'run unit tests'
)
option(
'vapi',
type : 'boolean', value : true,
description : 'Whether or not to build vapi files for gplugin'
)